The important steps involved in the fabrication process of a PCB start with design specifications and extend to choosing the right materials and manufacturer. This involves designing a layout of the circuit, usually with the use of CAD or Computer-Aided Design software, to help in the mapping of component placement with electrical connections. This is a very crucial step since a lot of money gets lost in revisions if something goes wrong in the layout. A designed file is then generated into a Gerber file. This format has become the standard in the industry for the communication of such vital information as copper layer data, solder mask layers, and drill holes from designers to fabricators. Many designers rely on Gerber files since they prevent possible inconsistencies between design and manufacturing.
Apart from the mentioned, basic issues in fabrication also include material selection. FR-4 is a common type of material, basically consisting of epoxy resin with fiberglass reinforcement, because it has a reasonable balance between durability and cost. Other types of materials, such as polyimide, allow for flexible PCBs, which are much needed in compact devices. The FR-4 thickness can range from 0.2 to 3.2mm, depending on the required strength and flexibility of the board. The selection of appropriate material helps the board to respond when subjected to thermal and mechanical stress. This is specifically true within the automotive industry, which usually has PCBs operating at much-increased temperatures. In this regard, it is reported that 35% of the failures in automotive electronics are caused by inappropriate selection of materials. Such alarming statistics put up the importance of selecting proper materials for intended operating conditions.
As soon as material and design are fixed, the next step is to select a reliable manufacturer. The good PCB manufacturer will provide quality certifications necessary for that particular industry, such as ISO 9001. Testing would include high-level testing capabilities: Automated Optical Inspection and electrical. For example, AOI can detect misalignments and microcracks with accuracies as high as 98%. This ensures every board strictly meets specifications. The ability to do this sort of test is really invaluable in an industry where even minor defects can result in failures. Many manufacturers provide options for prototype pcb fabrication in 24-48 hours for fast turnaround needs, thus allowing faster design validation and iteration. This capability becomes highly useful when dealing with industries that require rapid product development cycles, such as consumer electronics.
Also important is budgeting. The material cost ranges because of several variables: the number of layers, typically between 2 and 40 for both normal and advanced designs, and board thickness and complexity. Speaking generically, a 4-layer PCB costs about 20-30% more than its 2-layer counterpart because of the more material and manufacturing that is required. Designers are, therefore, always attempting to balance the desire for advanced functionality with budgetary requirements. This calls for transparency between design and manufacturing levels on the budget level so as to enable informed decisions without compromising quality.
The start of the manufacture of PCBs involves drafting and careful selection of materials, along with identification of a qualified manufacturer that will be responsible and ensure a reliable and cost-effective production process. These basic steps thus lay the foundation to make the performance, durability, and cost requirements of the fabricated boards meet the set requirements, thereby placing the project on a success path right from the very commencement.