A Detailed Overview of Copper Clad Laminate

 

1. What is Copper Clad Laminate?

Copper Clad Laminate (abbreviated CCL) is a base material for PCBs. A copper-clad panel is made by laminating glass fiber or wood paper with copper on one or both sides after the material has been soaked in resin.

Copper Clad Laminate

 

2. How are CCLs classified?

CCLs are classified according to different standards.

  1. We have rigid CCL (FR-4 CEM-1, etc.) based on the mechanical rigidity of CCL. Flex CCL. Flex PCBs rely on flex and rigid CCLs.
  2. We have organic resin CCL in FR-4 (FR-4), CEM-3 (CEM-3), etc., metal-base CCL, ceramic-base CCL, etc.
  3. We have two types of CCL based on thickness. The thickness of the former must be at least 0.5mm, while that of the latter may be less than 0.5mm. The CCL thickness does not account for copper foil thickness.
  4. We have glass fiber cloth CCL, paper CCL, and compound CCL.
  5. We have two types of CCL based on the insulation resin used: Phenolic (FR-1,XPC) and epoxy CCL.
  6.  

3. What makes a good CCL?

CCLs can only meet performance requirements when they are able to cater to the following:

  1. Appearance. Unexpected elements in the production process, like dents or scratches, resin points, wrinkles, pinholes, bubbles, etc., might have an impact on copper foil. These issues will all result in a poor CCL and, eventually, a PCB.A CCL that is excellent should have a flat, smooth appearance.
  2. Size. As CCLs are the base material for PCBboards, they must conform to the size requirements of PCBs. The size of CCLs is determined by several parameters, including length, width, and diagonal deviation.
  3. Electrical performance. It is essential that a PCB achieves this mission. Therefore, any factor affecting the electric performance of the board must be designed carefully. This includes dielectric constant, dielectric loss tangent, volume resistance, surface resistivity, insulation resistance, and arc resistance.
  4. Performance. The physical performance of CCLs is determined by dimensional stability (PS), peel strength (PS), bend strength, heat resistance, thermal stress (Td, T260, T288, and T300), punching qualities, etc.
  5. Chemical Performance. The chemical performance of CCLs must meet requirements such as flammability and chemical resistance to reagents, Tg, Z axis coefficient thermal expansion (Z CTE), dimensional stabilities, etc.
  6. Environmental performance. It must meet the requirements of water absorption, etc.

PCB Fab Houses should perform CCL quality judgment. AssemblePCB, for instance, uses IPC-4101C for manufacturing standards and IPC-TM-655 for CCL tests. CCLs are therefore qualified as PCB substrates when they meet these standards.

 

4. Prepreg: What is it?

Prepreg is the reinforcing material found within a CCL. It is baked and composed of glass fiber. Some people call it a bonding sheet, and it is composed of epoxy resin, DMF cloth, 2MI, Acetone, etc.

Classification of prepreg. There are many classification standards for prepreg.

1). Based on glass fibre cloth: 106; 1080; 2112; 2116. 1500 and 7628.

2). Based on the resin used and its performance, POLYCLAD Turbo254/226, ISOLAFR402/FR406,ITEQIT180, Sheng YiS1141-140/170

Resin Classification

1)Phenolic resin

2)Epoxy resin

3)Polyimide resin

4) Polytetrafluorethelene resin (PTFE or TEFLON resin)

5) Bismaleimide triazine (BT)

Glass Fiber is characterized by the following attributes:

1)High intensity

2) Fire and heat resistance

3) Humidity Resistance

4) Excellent insulation capabilities

Factors that affect the quality of prepreg. A high-quality prepreg will lead to a high-quality PCB, and then CCLs. AssemblePCB is very concerned with the quality of prepreg, and tests and controls it in terms of resin, gel time, and resin fluidity.

Select prereg according to cost. Glass fiber cloth is the main factor in the high cost of prepreg. In general, prepreg costs are directly correlated with the thickness and quality of the glass fiber cloth. The cost of prepreg increases as the thickness of the cloth decreases. Prepreg 1080 is cheaper than prepreg 1112 because it is rarely used.

评论

发表评论

此博客中的热门博文

The Complete Guide to 2025 PCB Assembly Costs

图片
  Concerned about the expense of PCB assembly? Precise PCB assembly estimations are crucial. Being aware of this can lower your expenses. You can use this advice to make well-informed judgments on cutting  PCB assembly  cost s . 1.  8 Key Factors Influencing PCBA Cost 1.1 PCB complexity （1） PCB layers Single-layer and double-layer PCBs are the least expensive. Due to increased material prices and routing complexity, multilayer PCBs are more costly.. According to the general belief, PCBs cost increases with increasing layers. （2） Dimensions PCB The size of the PCB determines its cost. The more space there is on the PCB, the easier it will be to add components and circuits for the intended purpose. Larger PCBs are more expensive because they can be used for large and medium devices. Smaller PCBs need fewer parts and are less expensive. As the PCB grows in size, the assembly costs increase. （3） PCB minimum hole diameter Drilling requires a drill bit. Compared to drill b...
阅读全文

Comprehensive Guide of PCB Silkscreen

图片
  In the intricate ecosystem of electronics manufacturing, the  Printed Circuit Board (PCB)  is often celebrated for its conductive copper pathways and protective solder mask. However, there is a “silent communicator” on the board that bridges the gap between complex hardware and human intelligence: the PCB Silkscreen. While it may seem like a mere aesthetic addition, the silkscreen layer (or legend) is a critical engineering component. For professional engineers, PhD researchers, and hardware students, understanding the nuances of silkscreen is essential for optimizing the assembly process, ensuring maintenance feasibility, and maintaining signal integrity in high-frequency designs. This guide provides an exhaustive technical analysis of every facet of the PCB silkscreen layer. At its technical core, the PCB silkscreen is a layer of non-conductive, specially formulated epoxy ink applied to the surface of a printed circuit board. The term itself originates from the tradit...
阅读全文
图片
A Complete Guide to Aluminum PCB   Aluminum PCB are built for heat. Learn what makes aluminum circuit boards essential for LEDs, power tech, and high-efficiency electronics. Aluminum PCBs don’t get much attention. They should. These boards are quietly powering LED lights, automotive electronics, power supply units, and so much more. Why? Because when things heat up, literally, aluminum circuit boards step in. Heat is the enemy of performance. If you’ve ever held the back of an LED lamp or a phone charger and noticed it’s warm but still working perfectly, you’ve probably encountered an  aluminum PCB  board without realising it. In this guide, I’m walking you through everything: what aluminum PCBs are, why they’re a smarter choice in high-heat environments, where they’re used, and how to avoid wasting money on low-grade options. Whether you’re sourcing for production or just exploring your options, you’ll want to understand how aluminum printed circuit boards have quietly b...
阅读全文