The ultra-large-scale integrated circuit factories in the world (called wafer factories in Taiwan, for the sake of simplicity, this article will also use this name) are mainly distributed in the United States, Japan, Western Europe, Singapore and Taiwan and other developed countries and Regions, in which the Taiwan region occupies a pivotal position.

The products produced by fabs actually include two major parts: wafer slices (also referred to as wafers) and VLSI chips (also referred to as chips). The former is just a smooth round sheet like a mirror. Strictly speaking, it has no direct practical application value. It is just a raw material for the subsequent deep processing of the chip production process. The latter is the final product directly used in many industries such as computers, electronics, and communications. It can include CPUs, memory units, and various other professional application chips.

1. Chip production process flow:

The manufacturing process of the chip can be roughly divided into several steps such as wafer processing process (WaferFabrication), wafer probing process (WaferProbe), packaging process (Packaging), testing process (InitialTest and FinalTest). Among them, the wafer processing process and the wafer probe test process are the front end (FrontEnd) processes, and the assembly process and the test process are the back end (BackEnd) processes.

1. Wafer processing process: The main work of this process is to make circuits and electronic components (such as transistors, capacitors, logic switches, etc.) on the wafer. The processing procedures are usually related to the type of product and the technology used. However, the general basic steps are to clean the wafer properly, then perform oxidation and chemical vapor deposition on the surface, and then perform repeated steps such as coating, exposure, development, etching, ion implantation, and metal sputtering, and finally on the wafer Complete processing and production of several layers of circuits and components.

2. Wafer probe test process: After the previous process, a small grid, that is, dies, is formed on the wafer. Generally, in order to facilitate testing and improve efficiency, it is made on the same wafer Products of the same variety and specifications; however, several products of different varieties and specifications can also be produced according to needs. After detecting the electrical characteristics of each die with a probe instrument, and marking the unqualified die, the wafer is cut and divided into individual die, and then according to its electrical characteristics Sort them into different trays, and discard unqualified dies.

3. Assembly process: Fix a single die on a plastic or ceramic chip base, and connect some lead terminals etched on the die with the protruding pins at the bottom of the base. As the connection with the external circuit board, the plastic cover is finally covered and sealed with glue. Its purpose is to protect the crystal grains from mechanical scratches or high temperature damage. At this point, it is counted as an integrated circuit chip (that is, those black or brown rectangular pieces with many pins or leads on two or four sides that we can see in a computer).

4. Testing process: The last process of chip manufacturing is testing, which can be divided into general testing and special testing. The former involves placing the packaged chip in various environments to test its electrical characteristics, such as power consumption, Running speed, pressure resistance, etc. The tested chips are divided into different levels according to their electrical characteristics. The special test is based on the technical parameters of the customer's special needs, taking out some chips from similar parameters, specifications and varieties, and doing targeted special tests to see if they can meet the special needs of customers, so as to determine whether they must be designed for customers chip. Products that have passed the general test can be shipped out after they are affixed with labels indicating specifications, model numbers, and date of manufacture, and packaged. Chips that fail the test are classified as degraded products or scraps depending on the parameters they reach.