prototype pcb technology in China
The development of semiconductor integrated circuits, the demand for miniaturization of electronic products, promote the development of micro-electronic assembly technologies, formed the three pillars of technology, ie, SMT, TAB, and of HIC. These three technologies are the progressive development and then to form a complete technology. First used in the hybrid integrated circuit leadless components, the manufacture of semiconductor devices using wire bonding (Wire Bonding) to connect the chip inside the head} line and the base of the outer lead bonding point J asked during the Second World War period, In order to find the fuse (Proximlify fuze) parts of the small memory, while Indo-Wei silver on ceramic substrate conduction band about 1943, the military formed with carbon resistor network these are surface mount technology, tape automated bonding, mixed integration The pcb prototype of the circuit. After years of development, has formed a high-tech, comprehensive three micro-assembly technology, and continuous improvement and development, a comprehensive basis of technology, including the following four aspects:
A. Components and materials
Such as surface mount components (SMC and SMD), must be in the surface mount technology based pull, solder paste, glue and other volumes with automatic keypad (TAB) tape and reel materials, conductive and non-conductive viscose; thick substrate in thin film hybrid circuits, conductors, resistors, dielectric materials.
Two. Equipment and processes
Three technologies, each have a dedicated equipment and processes, these are the technologies most critical part. Although the similarities of some equipment and technology, such as the printing press used by the SMT and the absorption membrane HIC, due to the used substrate flatness, size, choice of different equipment and processes of the pulp Division is not the same.
3. Detection technology
With the increased density of components, pcb assembly, components, the spacing between the leads is getting smaller, resulting in a corresponding detection technology. Automatic test equipment, such as online by a small computer, the controller and bed fixture tester Cheng.
4. Overall computer operations CIM (ComputerIntergrated Manufaeture) by the computer to control the entire production process. These three techniques, the use of SMT is the most widely used, the technology is perfected, and has entered the fine spacing (FinePitch,) phase, the spacing is less than to 0.63mm, 0.5mm, 0.3mm pitch components have a large number of mount . With the LSI complexity of the integration degree of increase I / O (input / output) foot increase in the number, spacing has become increasingly narrow, the QPF has been too too much to the quad flat package. Volumes with automatic keypad (TAB) technology, the chip mounted on the winding to bring the passage of the TAB package IC mounted to the printed circuit board, it can be easily 500-1000 pin, pitch 0.2mm- 0.1mm, and the price is very competitive, is a new generation of fine pitch assembly techniques. Thick film hybrid circuits used to implement integrated unit function circuit, or subsystems, the overall volume of electronic products shrink, debug manufacturing convenience.
Micro-miniaturization of electronic products need to be able to use these technologies specifically designed and manufactured processing companies need to spend a lot of manpower, financial investment. For some large companies may not be more difficult for SMEs. The needs of the market, large-scale socialized production and division of results, some small and medium-sized high-tech enterprises, undertake a "design" the heart and center of manufacturing and processing functions. Emergence of the so-called original design bureau ODM (Original Design Manufacturer) and commissioned by the manufacturer 0EM (Orignal Equipment Manufacturer) or a combination of these two areas the ability manufacturers, and has been very development.