Ceramic PCB capabilities
Ceramic Printed circuit board contains Alumina (Al2O3), Aluminum Nitride (AIN) PCB, as they have the high-pressure, high-insulation,high-frequency and high temperature performance.
We can build according to your requirements. You can understand us better with the below specific capabilities chart.
Comparison of Ceramic PCB with FR4
FR4 is the most commonly used board material, compared to ceramic multilayer board, what difference do they have? Let’s find out:
1. Thermal Conductivity (Wm-K): Ceramic PCB is 28-280; FR4 is 0.8-1.1
2.Frequency Performance: Ceramic PCB is high, FR4 is low
3.Availability: Ceramic PCB is low, FR4 is high
4. Cost:Ceramic PCB is mid-high, FR4 is Low-mid
Venture Ceramic PCB
Venture is a professional Ceramic PCB fabrication manufacturer for more than 10 years. We provide ceramic PCB design and fabrication using our advanced complete software designs. Through the high development of electronics and telecommunications, Venture high-quality ceramic PCB is highly required by most customers.
Our well-trained professional designer team offers reliable quality ceramic PCB such as multilayer ceramic PCB, thick film ceramic PCB, ceramic PCB China, OSP PCB, Enig PCB (Immersion gold PCB), immersion tin PCB, immersion silver PCB, cheap flex PCB , thin PCB ultra-thin PCB, custom PCB boards, single-sided PCB, double-sided PCB, and more. Through the use of high-technology, we can produce a high-quality and reliable ceramic PCB.
Mainly, Venture ceramic PCB is a printed circuit board with a ceramic base material. Our Ceramic PCB can make a quick effect on transferring heat away from hot spots and dissipating it over the whole surface.
Venture: Your Best Ceramic PCB Supplier in China
As a professional supplier and manufacturer, Venture is able to produce high-quality Ceramic PCB that will suit your needs. We are an expert when it comes to manufacturing different types of Ceramic PCB. Our Ceramic PCB includes:
- Multilayer ceramic PCB
- Thick film Ceramic PCB
- Ceramic PCB China
- OSP PCB
- Enig PCB (Immersion gold PCB)
- Immersion Tin PCB
- Immersion Silver PCB
- Cheap Flex PCB Cheap Flexible PCB
- Thin PCB Ultra-Thin PCB
- Custom PCB boards
- Single-sided PCB
- Double-sided PCB
Venture Ceramic PCB can provide you to enjoy their greatest implementation in high-speed, high-power circuit applications. Also, these boards have been shown to reduce parasitic capacitance by up to 90%.
Mainly, Venture Ceramic PCB has a primary advantage of ceramic multilayer PCBs lies in their thermal properties. Our Ceramic PCB is compared with the ceramic multilayer board in a number of important categories.
Our Ceramic PCB is also suitable for high current applications. These also feature thermal conductivity, which outperforms traditional materials by a tremendous margin. It is also a continued increase in the use of ceramic boards for high-speed and high-power applications.
If you want to request a Ceramic PCB and have detailed specifications in mind, the Venture Electronics Design Team is much willing to help you.
We also have well-trained Layout Engineers to help you match your design drawings and schematic files. We are committed to enhancing prototyping by the production process to quote and delivery.
Whether you are a maker, system integrator, product designer, or electrical engineer looking for a cost-effective Ceramic PCB, Venture Electronics is your best manufacturer in China!
We have more than 10 years of being a turnkey Ceramic PCB solution provider in China. As a professional manufacturer, we can provide unmatched customer services.
Feel free to contact us if you have more inquiries about our Ceramic PCB!
Ceramic PCB: The Ultimate FAQ Guide
In this guide, you will find all information you have been looking for about ceramic PCB.
Whether you want to learn about the fabrication process, features, identification or types of ceramic printed circuit boards, you’ll find everything here.
Keep reading if you want to be a ceramic PCB expert.
- What is Ceramic PCB?
- Where are Ceramic PCBs Used?
- What are the Qualities of Ceramic PCB?
- What Challenges are Associated with Ceramic PCBs?
- How can you Identify a Good Ceramic PCB?
- What are the Types of Ceramic PCB?
- What Materials are used to make Ceramic PCB?
- What is a DBC Ceramic PCB?
- Is using the DBC Ceramic PCB Advantageous?
- How is a Multilayer LTCC PCB made?
- What is Solder Paste Stenciling?
- How do you Solder Ceramic PCB?
- What the Properties of Ceramic PCBs?
- How is the Conductive Track Laid on the Ceramic PCB?
- What are the Considerations for a Ceramic PCB design?
- How does the Ceramic PCB compare to the Traditional PCB?
- What are some of the Process involved in Fabricating Ceramic PCBs?
- How do you Laminate Ceramic PCB?
- Why is Ceramic PCB Design Important?
- How can you Drill Ceramic PCB?
- What are some of the Features of a Ceramic PCB?
- What Semiconductor Packages are used for the Ceramic PCB?
- How is Quality Control carried out on Ceramic PCBs?
- How do you Test Ceramic PCB?
- What are the Key Considerations when Inspecting Ceramic PCB?
What is Ceramic PCB?
Ceramic compounds are used instead of the typical FR-4 material used in common PCB designs reducing board complexity.
The ceramic compounds used are metal based such as aluminium nitride and oxide.
Some of the qualities you achieve with ceramic-based circuit boards include remarkable thermal qualities and impressive electrical isolation.
The conductive paths used for ceramic PCBs are made from copper, silver and gold to mention a few.
The conductive tracks can also be enclosed in glass to offer protection from elements.
Copper is commonly used due to its availability and low cost.
Besides, silver is easily susceptible to external factors whereas gold is highly valued.
Where are Ceramic PCBs Used?
The venerable strength qualities possessed by ceramic circuit boards and their thermal and electrical performance allows their use in various applications.
This type of PCB is preferred for its incident free ability and dependability.
Additionally, it has low maintenance costs with impressive resilience to eternal environmental factors such as temperature and moisture.
You will also find ceramic PCBs especially useful in applications requiring high values for pressure and frequency.
Some of the applications are as follows:
- Power applications such as DC/AC modules, industrial equipment, automotive regulators, transistors and controllers.
- In LED applications requiring large currents.
- Refrigeration appliances that are semiconductor-based.
- Amplifiers especially those used for audio amplification.
- In exchange converters, oscillators and integrated chip arrays.
- As substrates for solar cells, integrated relays and variable optical devices.
What are the Qualities of Ceramic PCB?
You find ceramic PCBs possess the following merits that make their use popular in PCB construction:
Printed circuit board
- Ceramic PCBs have the exemplary ability of working at elevated temperatures.
Regular boards have their functionality impaired with increased temperatures.
The ceramic PCB canoperate without failing at extreme temperature values.
- Another quality aspect of ceramic PCBs is their low coefficient of expansion. You find that subjecting a ceramic PCB to varying temperature values will have no significant structural change. As such, there’s is less chance ofoccurrence of structural deformation with the use of ceramic PCBs.
- Using ceramic PCBs you note their impressive thermal transfer capabilities. It follows that, these board types are effective in removing dissipated heat from the board structure.
Consequently, you do not expect the manifestation of thermal strains as a result of heat buildup.
- The performance of ceramic PCBs at high-frequencies is admirable.
When you need to consider aspects related to transmission impedance and the communication bandwidth especially.
Ceramic PCBs augment the board’s response to signal interference.
- Making ceramic PCBs in multiple layers is uncomplicated.
You find that ceramic possesses superior mechanical strength that can support a stack up of several layers.
A higher layer count allows a ceramic PCB to have a larger circuitry and component density.
This allows its use in complex applications with high performance demands.
- While traditional PCBs can succumb to the unpredictability of voltage values, the ceramic PCB is an exception.
You will find the ceramic PCB can tolerate voltage inconsistencies thus offering device protection.
Besides, their inferior electrical conductivity provides effectual resistance to electrical charge flow across layers.
- You will find the capability of ceramic printed circuit boards to bear elevated radiation exposure is high.
Consequently, the use of ceramic PCBs in space modules and satellites is common.
This is because ceramic circuit boards can be relied upon to function continuously without failure in that environment.
- Ceramic-based printed circuit boards can be furnished in smaller designs with elaborate circuits.
Additionally, you can duplicate processes involved in a single layer for a multilayer PCB greatly reducing costs.
The board performance is positively affected with these measures.
- Ceramic material cannot take up external moisture content due to their low constant of dielectric.
Therefore, you will find ceramic boards are not susceptible to property constraints resulting from water presence.
In other substrate materials, water content affects dielectric properties.
What Challenges are Associated with Ceramic PCBs?
While it has desirable qualities, the ceramic PCB is associated with the following limitations:
- Ceramic-based circuit boards are impaired with the fragile structural build. This means that the ceramic PCB can easily break.
You will, therefore, hardly find large ceramic PCBs.
- Another discernable limitation of the ceramic PCB is its associated costs. While the fabrication processes involved are less, the processes have high attached costs resulting in an expensive product.
How can you Identify a Good Ceramic PCB?
The following features will help you to identify a ceramic PCB that is of good quality:
Custom ceramic PCB
- The board’s circuit pattern will provide a measure of the board quality.
The conductive path must be practical for the achievement of the intended application.
A ceramic PCB intended for a large power application should have wider circuit traces for example.
Additionally, the spacing between traces and the margin clearance should also convey the application needs.
- The presentation of the board is also a significant indicator of its quality.
A quality ceramic circuit board should have a smooth finish with no visible bumps and contusions.
Furthermore, there should be no cracks and crevices on the board surface.
You also find the placement of components can speak to the quality of the ceramic PCB.
Missing components and misaligned components will indicate a lack of inspection and as a result a deficiency in quality.
- The thermal qualities of the ceramic PCB especially resistance to heat.
While ceramic circuit boards are said to have good thermal properties, you cannot take the manufacturer’s word for it.
Individual examination of the board is crucial to determine the truth of the maker.
Consider, a scenario calling for manual soldering of the ceramic circuit board.
The board should be unaffected by the heat generate by the soldering process for a quality board.
However, a defective board will exhibit failure to withstand the heat by forming a heat bump or pocket.
- The response of the board size and structure to temperature variations.
This is a mark of the board’s coefficient of expansion.
Quality ceramic PCBs have low CTE making them unresponsive to temperature shifts.
This way, whether in hot or cold conditions, the board structure and size remain the same.
Poor quality boards will alter their shapes and sizes with temperature fluctuations.
High temperatures will result in material expansion and consequently impact the board size.
A reduction in temperature on the other hand will induce a board reduction in size.
This will eventually lead to structural deformation due to different expansion rates.
What are the Types of Ceramic PCB?
You will find a variety of ceramic PCBs having different structural designs and involving different fabrication processes.
Some typical ceramic-based printed circuit boards include:
· Single-sided Board
This is the standard board design for a ceramic PCB in which case there is only a single conductive layer.
With this design, it is typical to find the board populated on one side while the alternative side is utilized for routing.
· Double-sided Board
The double-sided board is a modification of the single-sided board allowing for an increased circuit density.
With this ceramic board design, there is a brace of conductive surfaces.
This allows the population of both levels allowing for use in applications requiring higher component counts.
· Multi-layer Board
A multilayer ceramic printed circuit board is one whose conductive levels exceeds two.
The layers are categorized into external and internal layers, where the excess conductive levels are located.
Also, the layers are usually even in number such as four layers, six layers, and eight layers, and so on.
The even nomenclature is due to the fact that the layers are fabricated over a core of non-conductive material.
Thus, the ceramic layers will be odd in number.
This formation suits sophisticated and demanding applications.
· Thick Film PCB
Thick film ceramic PCB formation entails a baking procedure in a gas heated oven at temperatures of about 900 oC.
Nitrogen is used in the gas mixture to deter the formation of oxide layers.
You find this process is efficiently carried out for large quantity processing.
To form a thick film ceramic-based PCB, gold or dielectric material is utilized as thick matter.
While gold provides impressive performance, its use is limited because of its cost.
This ceramic board type is one of the most effective and conversely popular.
· HTCC (High-Temperature Co-fired Ceramic) PCB
Co-firing is a manufacturing process that involves subjecting material combinations to heat treatment.
When this process is carried out at elevated temperatures it is referred to as high-temperature co-firing.
HTCC PCBs are board from ceramics treated through this process.
Such ceramic material is formed through rolling and layering process that is preceded many instrumental processes.
These processes involve high temperature and pressure values such as laminating and oven baking.
PCBs made in this nature are normally small sized due to the difficultly in furnishing larger boards that are functionally effective.
Additionally, this PCB type can be used for secondary and slave PCBs and.
You can find conductive metals such as tungsten used for circuitry but this will be adversely affected by the board’s resistance.
A major drawback of this ceramic PCB is its vulnerability to thermal strains alongside a predilection to undesired shrinkage.
· LTCC (Low –Temperature Co-fired Ceramic) PCB
This ceramic board type is similar in process to the HTCC PCB.
The major difference is the employment of reduced temperatures in this case and the material composition.
LTCC PCBs are commonly fabricated from the combination of adhesive substances with glass derivatives.
When the fabricated boards are panelized, they are baked in an oven that is gas heated.
The temperature conditions are low for oven standards at about 850 oC.
The conductive material for use with this PCB type should be an excellent conductor such as gold.
LTCC PCBs have the advantage of adhering better with the conductive material that is pivotal for laying the circuitry work.
Moreover, the material is less susceptible to shrinkage as a result of structural inefficiencies.
What Materials are used to make Ceramic PCB?
There are three material compounds commonly utilized as the board substrate for ceramic PCBs.
Aluminium oxide, aluminium nitride and beryllium oxide.
However, beryllium oxide contains poisonous elements established to be harmful to the environment leading to departure from its use.
From the remaining two compounds, you find aluminium oxide is more commonly used by ceramic PCB manufacturers.
Some of the qualities identified with its usage include:
- The abundance of aluminium metal and the relatively simple process of making aluminium oxide makes it a widely available compound.
- Aluminium oxide has poor electrical conductivity thus offering the desired isolation between conductors.
- The structural composition of aluminium oxide gives it good mechanical attributes with a good strength to weight ratio.
- You will appreciate the ability of aluminium oxide to withstand compressive forces.
- Additionally, alumina, as it is also called, is highly resistant to chemically induced deterioration and physical mutilation.
- The thermal transfer capabilities of aluminium oxide are highly regarded.
As such, a substrate formation of aluminium oxide dissuades heat buildup in a ceramic-based PCB.
- Aluminium oxide displays high temperature affinity retaining its structural integrity at temperature values of over a thousand degrees centigrade.
Aluminium nitride, on the other hand, shares most of the physical, electrical, and thermal attributes with aluminium oxide.
However, use of aluminium nitride is limited due to its cost.
Producing aluminium nitride is an expensive undertaking that reflects in its pricing.
Beryllium oxide offers remarkable electrical insulation for conductive levels.
Furthermore, its thermal transfer property is unrivalled by many materials including both metals and non-metals.
What is a DBC Ceramic PCB?
A DBC ceramic PCB is a directly bonded copper ceramic printed circuit board.
This special type of ceramic PCB has a copper plate attached to the fine ceramic layer under temperature and pressure.
The copper film can be attached on either one or both surfaces of the fine ceramic enhancing the PCB’s mechanical strength.
You will find the resulting substrate formed by bonding copper to the fine ceramic has superior qualities.
This include, impressive heat conductivity, exceptional electrical insulation, outstanding attachment strength and good solderability.
Additionally, you can etch the bonded copper to form a conductive path with the ability to conduct large currents.
Is using the DBC Ceramic PCB Advantageous?
Yes, it is.
You find that other than the outstanding mechanical, electrical and thermal properties, the DBC has the following pros:
- The DBC ceramic PCB achieves a high thermal cycling count upwards of thousands of cycles reflecting its reliability.
- Chemical infringement in the form of corrosion is unlikely to affect the DBC ceramic PCB due to its high resistance. It is also resistant to external contaminates.
- You can use the DBC ceramic PCB within wide operating temperature ranges of between -50oC and 900 o
- The DBC ceramic PCB has a matching CTE with semi conductor based chips allowing their direct attachment to the board surface.
This approach eliminates the need of an interface level for the attachment of semiconductor devices hence saving costs.
- Additionally, the DBC ceramic PCB features lesser value trace parameters for similar current demands to a standard ceramic PCB.
- With the DBC ceramic PCB, the overall power output per unit volume is higher resulting in a more reliable service performance.
- The temperature values registered for every unit current increase for a directly bonded copper circuit board is low. This makes this board type suitable for large power applications.
How is a Multilayer LTCC PCB made?
Multi-layer ceramic PCB
The LTCC PCB is a low temperature co-fired ceramic circuit board that is sintered at low temperature values.
These ceramic compounds are co-fired alongside metallic elements with excellent conductivity such as gold at temperatures of about 900 oC.
You will find applications of a high frequency nature and with microwave signal transmissions encompassing LTCC PCB.
These ceramic board type can be stacked for several layers while still offering superb physical and electrical attributes.
Moreover, furnishing this ceramic PCB in multilayers allows for its use in portable devices with excellent frequency transmissions.
Alongside its compatibility with embedded devices such as passive components, you can make the trace pattern using ultra-thin wiring.
To make the multilayer LTCC PCB, individual layers are handled separately before being stacked and bound together.
The layers consisting of the conductive layers, prepreg and substrates are drilled for vias followed by punching and filling.
Types of vias
Each conductive layer follows a printing process, where the desired conductive path is determined.
The layers are then optically inspected for errors and faults such as holing deficiencies and trace misalignment to mention a few.
Upon successful inspection, the layers are configured in a stack according to the desired signal order.
The conductive layers are separated from the insulating layers with prepreg material that acts as bonding agent during lamination.
Lamination is carried out in heated gas ovens under pressure.
The conditions are just enough to soften the prepreg without wholly melting it.
Also, the stack is then sintered and when cooled the prepreg sets forming a bond between the layers.
The now single structure board is then finally inspected and tested for its electrical, thermal and mechanical aspects.
A computer controlled vision system is used for optical inspection while a flying probe is employed for electrical testing.
What is Solder Paste Stenciling?
Solder paste stenciling is a process used to mark out the requisite board parts for paste application.
The solder paste is composed of flux which is used as a cleaning agent for the identified surface locations.
It also inhibits oxidation.
Additionally, stenciling of the board allows the solder mask to be appropriately laid out.
This way, the placement of components is easily carried out without interference to other board structures.
How do you Solder Ceramic PCB?
The soldering process of a ceramic PCB is specific to the component types.
You will find through-hole components undergo a different soldering method in comparison to surface mounted components.
As a result, two soldering processes are determined.
Reflow soldering is particular to unleaded components attached to the board surface over solder pads.
In carrying out reflow soldering, the solder paste is applied over the solder pads before components are attached to them.
The board with attached components is then conveyed to an oven whose heat components melts the paste.
This process is described as reflow and it adheres the mounted component to the board surface when cooled.
With through-hole components, wave soldering is used.
The component leads are hooked to the alternate board side where they are soldered.
The paste is applied by robotic arms before being melted in heated ovens.
Through-hole components can also be soldered manually.
What the Properties of Ceramic PCBs?
The ceramic-based board has the following useful features that makes it useful in electronic making:
- You find drilling of through-holes in ceramic PCBs is easier without the problem of flux smear even at high drilling temperature.
- Printed circuit boards with ceramic substrates can be fashioned in a variety of PCB design formations. You can find a single-sided ceramic circuit board and one with several layers.
- Using ceramics can support large-scale production with the fabrication of large panel sizes that can be cut.
- You are able to make smaller sized vias in ceramic PCBs without difficulty as you would with non-ceramic substrates.
Furthermore, these vias can be blind vias connecting surface and internal levels and buried vias connecting internal levels.
- Copper adheres well to ceramic-based boards allowing their use as conductors. Additionally, you can use heavy copper to conduct larger currents and regulate the board’s impedance levels.
How is the Conductive Track Laid on the Ceramic PCB?
The conductive path on a ceramic printed circuit board can be based on a thin foil or a thick foil.
The foil size influences the thickness of the conductive path and consequently, the amount of current allowed.
To lay the conductive track using thin copper foil, you have to develop a pattern for the conductive path first.
There are different approaches in developing the pattern.
You can use a lithographic approach or enlist a magnetic driven technique.
Additionally, an etching process can be used to develop the conductive path using the thin copper foil.
Alternatively, the film can be electroplated with copper in the desired pattern.
This approach also influences the thickness of the trace.
For a thick copper foil, laying the conductive path can be guided by high or low temperature co-firing.
In this case, the copper foil and ceramic substrate are subjected to temperature treatments that binds them together.
What are the Considerations for a Ceramic PCB design?
The design and layout of PCB slightly differs from other boards using different substrates.
You would find the following procedures in their design process.
PCB design and layout
- The selection of material for the conductive layer of the ceramic PCB is important. Copper is preferred due to its remarkable conductivity and wide availability.
Moreover, a variety of copper weights can be used on the ceramic PCB.
- Additionally, another design consideration of the ceramic circuit board is the conductive track’s parameters. The parameters in view here relate to the width of the conductive track and the space allowed between tracks. You note that these parameters are dependent on the weight of copper used.
- Of equal importance as you would expect is the size of the board. The board size will depend on the intended application of the ceramic PCB.
Additionally, the quantities to be produce and the ease of fabrication will factor in.
Large production quantities can allow for the fabrication of large panels that will be cut into size.
- Another consideration is the space allowed between the conductive paths on the board surface and the board boundary.
Sufficient space should be allowed between the board ends and the conductive track.
As a rule, the thickness of the conductive track dictates the space allowed.
- Also imperative is the finish you intend for the board surface.
You will do well to have a combined finish of gold and nickel for your ceramic PCB.
These finishing options provide good surface quality for the PCB.
How does the Ceramic PCB compare to the Traditional PCB?
The ceramic-based PCB’s main point of difference with the traditional PCB is in the nature of substrate material.
You find that ceramic PCBs employ fine ceramic compounds such as aluminium oxide and aluminium nitride for its substrate.
Contrarily, substrates such as FR-4 and polyimide are used for the traditional printed circuit boards.
While they both have remarkable qualities suited for their application performance, you find the following performance contrasts:
Ceramic PCB for optical module
- The non-ceramic PCBs face the difficulty of handling temperature build-up within its structure.
Their material qualities and design limitations limit their ability to effectively dissipate generated heat.
On the other hand, ceramic circuit boards have excellent thermal conductivity that allows effective thermal transference from the PCB structure.
You find the ceramic boards outperform traditional PCBs tens of times when it comes to thermal conductivity.
- Printed circuit board parts are typically made of different materials, from the layer formation to the board populates.
These materials possess different thermal coefficients of expansion and as a result respond differently to temperature changes.
You find traditional PCBs are faced with a challenge of mismatching CTEs that leads to thermal strains manifesting in the board.
Alternatively, the impressive thermal properties of the ceramic PCB allows it to correspond effectively with other board materials.
- Additionally, the ceramic PCB is resistant to external infractions such as temperature and moisture absorption.
Traditional PCBs are affected by environmental factors such as humidity and temperature which affects its dielectric properties.
You find that in humid environments, substrate materials such as FR-4 used in traditional PCBs will take up moisture content.
This affects dielectric properties such as the dielectric constant and permittivity significantly hampering thermal conductivity.
- Furthermore, the strength performance of ceramic PCBs is to be admired over traditional circuit boards.
The traditional substrate materials perform poorly with regard to shear and tensile strength in comparison to ceramic PCBs.
You find ceramic circuit boards have higher shear strength values with an outstanding strength to weight ration.
This makes the fabrication of lighter but stronger printed circuit boards possible.
- Ceramic circuit boards are resistant to chemical infringement that can results in corrosion and adversely affect the board structure and functionality.
Traditional boards succumb to chemical impingement and as a result exposure to such chemicals is to be avoided.
You find that corrosion destabilizes the board structure of a traditional PCB by affecting the substrate properties.
Consequently, the board performance is affected and can result in board failure in extreme situations.
What are some of the Process involved in Fabricating Ceramic PCBs?
Fabrication of ceramic printed circuit boards involves several processes some of which are highlighted as follows:
Drilling involves the creation of through holes for two major purposes.
The holes can be used for component attachment and also to provide interlayer connectivity.
Interlayer connectivity is vital for both electrical charge transfer and thermal transference.
Drilled holes can be plain or metallized.
Non-plated holes are used for component fixation.
Plated holes offer a path for conduction of electric signals or heat transfer.
The holes used for connecting layers are also referred to as vias.
In this process, the desired pattern of the conductive trace is established beginning with the creation of a light sensitive sheet.
The sheet is developed through pressing of an inhibited film.
Using ultra violet radiation, an image is transferred to the sheet in the desired pattern
Every layer will have a pattern according to its designated function.
Consequently, you will not necessarily have similar patterns for the different levels.
For planes used in power and ground transmission, the pattern imaged will be unalike to those employed for signal transfer.
This is essentially a subtractive process where the copper foil part that does not make the desired pattern is extracted.
To aid in the removal of this part, chemical agents such as acid based solutions are used.
You find that in etching, a mask in the desired conductive pattern is placed over the copper foil.
This protects the desired surface from chemical interaction which eats away the undesired metal surface.
On completion of the process, the mask is removed exposing the pattern.
Several coatings are layered over the conductive surface of the ceramic circuit board.
A mask is used to cover the trace pattern to prevent it from interacting with flux during the soldering process.
Additionally, it inhibits the oxidation of the conductive metal.
Another layer called the silkscreen is also applied over the solder mask.
With this layer, information pertaining to the ceramic PCB is provided identifying parts components and other related details.
How do you Laminate Ceramic PCB?
The lamination process involves presenting a single structure for the final ceramic PCB.
In this process, several layers are combined under high temperature and pressure.
Both substrates and conductive layers are attached together in this procedure.
Ceramic PCBs are based on aluminium oxide or aluminium nitride substrates.
These ceramic compounds are semi-cured by a baking process alongside prepregs.
The conductive foils are then attached to the substrate surfaces.
The conductive paths are made by etching.
Before bonding the layers together, they are arranged in a stack according to the desired configuration.
For example, conductive levels for signals can be arranged adjacent to levels for grounds and power.
Once the stacks are secured by clamping, they are cured in an oven where the prepreg sets binding the layers together.
Curing is done under set temperature and pressure conditions to ensure the prepreg does not melt completely.
What is the Thickness of Substrates used in Fabricating Ceramic PCBs?
You find aluminium oxide and aluminium nitride as the two common substrates used in the fabrication of ceramic-based circuit boards.
Typical substrate thickness is pegged at about 0.0098 inches.
However, furnishing this thickness is expensive.
Instead, you find a range of substrate thickness that can be provided for ceramic boards.
Thickness can range from 0.015 inches to 0.05 inches with a preferred standard thickness of 0.025 inches.
However, the thickness will depend on the desired board qualities.
Why is Ceramic PCB Design Important?
The intended use of the board guides the board design process.
In designing a ceramic PCB, the desired qualities of the board are furnished to detail.
Some of the aspects that guide board design include the current carrying ability and the signal requirements.
Board design can be conducted by using specially developed computer programmes.
These programmes can help establish the trace parameters such as width and spacing depending on current needs.
Additionally, you can establish the layer count and population density.
How can you Drill Ceramic PCB?
Drilling involves the use of drill machines to make holes at appointed locations on the board.
The holes are drilled with reference to the established board design.
Due to the importance of drilled holes in relation to component placing and interlayer connectivity, accuracy is desired.
In achieving accuracy, the board’s surface design can be fed to a computer connected to a locator.
This locator utilizes x-rays to highlight the drill points on the board surface. Drilling is then carried out on the board.
The drilling process can be carried out manually or by computer controlled drilling machines depending on the volumes.
Drill bits are selected according to the desired size of the hole. A coolant is used to regulate the drilling temperature as a result of friction.
An important drilling aspect is that for a multilayer board, drilling is carried out in two phases.
First, holes are independently made before lamination for individual layers.
Later, after the layers have been combined, holes traversing the whole board structure are made.
Ceramic PCB with holes
What are some of the Features of a Ceramic PCB?
You find the following features attached to ceramic PCBs:
- High aluminium oxide content of about ninety eight percent.
- Wide variety of associated technologies such as thick film and thin film.
- A wide working temperature range of between -50 oC – 900o
- A low thermal coefficient of expansion of about 7 ppm/K.
- A large compressive strength capacity of over 4000 psi.
- High value range for thermal conductive from 25 W/m-K up to 250 W/m-K achievable when using aluminium nitride.
- A high breakdown voltage of about 28 KV/mm.
What are the Advanced Ceramic PCB Assembly Process?
The assembly process seeks to attach components and parts to the ceramic circuit board surface.
These parts and components are essential to the functioning of the board in its respective application.
Among the advanced assembly processes, you will find:
Die attachment equipment that involve bonding through printing and dispensing of epoxy and stamping.
You will also find soldering processes carried out via pre-formations.
Additionally, in die attachment, equipment with high accuracy levels are used to pick, place and pack parts.
Die encapsulation refers to the mechanisms put in place to safeguard the attached die.
A major encapsulation technique is curing in high temperature ovens or using ultra violet rays.
Also, under-filling the die base can work similar to coating the die and providing attached lids.
Wire bonding is also carried out as an advanced assembly process. In this instance, threadlike wires made of aluminium are used for micro-bonding.
Furthermore, aural wedge bonding that is temperature induced is carried out using lightweight gold wires.
What Semiconductor Packages are used for the Ceramic PCB?
The available semiconductor packaging are specific to your demands.
There are many packages that are utilized for the different input and output configurations available on the ceramic circuit board.
· Ball Grid Array Packages
The ball grid array package consist of small spherical attachments made of solder on the board surface.
These balls typically provide a surface connection to chip bottoms.
Ball grid array packages can be high voltage and stacked die and offer impressive speed performance.
· Land Grid Array (LGA)
The LGA is a pin configuration on the board surface that consists of oblong contacts referred to as lands.
It can be fabricated over a socket or connected to the board directly via soldering.
The LGA package is such that attachment of all the lands to a component is not a must.
Castellation are cut holes located at the board’s periphery used in providing locations for mounting secondary PCBs.
Castellations can also be used as guides for alignment purposes when soldering during an assembly procedure.
· Single and Dual In-Line Packages
A single in-line package consists of a strip of sockets used to accommodate board peripherals with solitary row of pin fixtures.
Dual in-line packages are similar to single in-line packages but with two parallel strips of sockets.
Attached peripherals have two parallel rows of pin joints.
· Quad Flat Packages (QFP)
This package type is attached to the circuit board for quadrilateral components with extending pin profiles from all sides.
The pin profile is close requiring careful handling during the attachment process when soldering to prevent bridge formation.
How is Quality Control carried out on Ceramic PCBs?
Quality control seeks to establish a functional ceramic-based board that is according to the design requirements.
In checking for quality, errors and faults are identified and corrected before the board is supplied.
A common approach in assessing a board quality is by carrying out inspection.
A board can be visually inspected by a quality controller with knowledge of the board design and structure.
It can also be automatically inspected via cameras and x-rays.
Missing components, misalignments and misplacements can be identified through visual inspection.
Poor solder joints can also be recognized.
However, this method is limited to small volumes of ceramic PCBs due to the element of exhaustion and time.
Automated inspection can be conducted by implementing a camera network that captures every board aspect.
The cameras capture the board and a computer compares the images to the programmed design standard identifying faults and errors.
Besides, automated inspection can be carried out using x-rays.
An emission machine controlled by a computer with the board design highlights the rays on the board.
It identifies faults and errors by comparison to the actual board design.
You find that through automated inspection using x-rays, electrical faults such as shorts and opens can be identified.
This is in addition to component related failings.
You can inspect large volumes of ceramic PCBs at more pronounced accuracy compared to manual inspection.
How do you Test Ceramic PCB?
Testing the ceramic printed circuit board is imperative to deliver a reliably functioning board of appropriate quality.
In testing, a variety of board aspects are examined include its mechanical strength and electrical performance.
Some of the tests conducted include:
- Optical inspection of the ceramic circuit board surface to identify errors such as omissions, component misplacements and misalignments.
- A grinding of the ceramic PCB’s side view.
- A cycling test to establish working temperature carried out between -70 oC and 250o
- You also find the board is tested for its tolerance to shear and pulling forces.
- A ceramic PCB is also subjected to x-ray observation and scanning.
- An electrical test is carried out via a flying probe to determine faults in the electrical system.
- The board is examined for its exposure to and presence of contaminants.
- You also find test systems established for determining the board response under pressure conditions.
What are the Key Considerations when Inspecting Ceramic PCB?
Inspecting a ceramic circuit board is a care demanding process that needs to be conducted under the guidance of defined rules.
It follows that you should consider the following when inspecting a ceramic-based PCB:
- It is important for you to identify the relationship of integrated components and their on-board communication network.
This way you can identify an error or fault when conducting inspection.
Some aspect to identify are the electrical parameters and pin information.
- Also of importance is the leads of mounted electronic components.
Their length should be enough to provide an attachment through the plated through hole.
Similarly, they should not be overly long such that they could result in undesired coupling effect.
- When manually inspecting the board, before using a soldering iron you need to establish its insulation properties.
Furthermore, it is prudent to employ a circuit with a reduced voltage count while making sure the soldering case is grounded.
- While carrying out electrical tests, care has to be taken to prevent shorting of pin connections.
Shorting can occur as a result of sliding when an oscillating probe is used for voltage measurement and determination of waveforms.
This is especially true for surface mounted chips.
- Direct coupling of integrated chips on the ceramic PCB surface can trigger a reading of different voltage values.
When inspecting the printed circuit board, this should not be construed for damaged components.
Contrarily, voltage readings should not be taken for sound components as some faults will barely affect the voltage readings.
- You need to ensure a large resistance deficit of instruments used in testing the boards. For example, when determining the voltage values of the ceramic board components the voltmeter should have a larger resistance value. This reduces the error value when taking measurements.
- Another important consideration is the ceramic PCB’s dissipation factor.
Heat is primarily generated by the board populates that have large power demands.
While the thermal transference of the ceramic PCB is impressive, large thermal dissipations necessitate the inclusion of a heat sink.
- The quality of the welds should be up to par during board inspection. Instances of heaped solder across the board are undesirable as they could create unwanted joints. You can use an ohmmeter to establish unwanted connections brought about by solder welds.
What can Contribute to Poor Performance of Ceramic PCB?
A ceramic circuit board when made to quality standards offers impressive functionality.
However, there are certain aspects that can hamper the quality of a ceramic PCB resulting in a poor and unreliable product.
You find the following factors responsible for such a calamitous result:
- Selection and usage of sub-standard materials for the ceramic PCB.
Fine ceramics are manufactured through combination of elements such as aluminium oxide and aluminium nitride.
Incorrect mixtures of the elements can result in poorly prepared materials.
Such materials will result in undesired outcomes such as board warpage.
Furthermore, you will also find boards of disproportionate sizes and uneven surfaces.
- The quality of a ceramic PCB will also depend on the equipment used in the production process and the accompanying technology.
Use of nondescript equipment will result in poor quality ceramic PCBs due to the lack ofprecision and efficiency.
For example, computer controlled and computer aided equipment have greatly improved the efficiency and accuracy of ceramic PCBs.
As such, there is a large difference in quality when the same processes are carried out mechanically without aided automation.
Here at Venture Electronics, we focus on designing and fabricating high performance ceramic PCB.
Contact us today for custom ceramic printed circuit board designs.