Embedded background - chip

CPU The manufacturing process of chips ：

1.CPU The raw material for chip manufacturing is silicon dioxide, which exists most in the earth's crust , From silicon dioxide to chip, it goes through the following processes ：
silicon dioxide ——> polysilicon ——> wafer ——> chip
2. Wafer manufacturing process ：
wafer ： Wafer refers to the silicon wafer used in the production of silicon semiconductor integrated circuits , Because its shape is round , So it's called wafer ; On silicon wafer, it can be processed into various circuit component structures , And become one with specific electrical functions IC product . The original material of the wafer is silicon , And there's an inexhaustible amount of silica on the surface of the earth's crust . Silicon dioxide ore is refined by electric arc furnace , Hydrochloric acid chlorination , And after distillation , High purity polysilicon is made , Its purity is as high as 99.999999999%
Wafer manufacturing process
（1） Deoxygenation and purification
sand / Quartz is deoxidized and purified to obtain silicon content 25% Of SiO2 silicon dioxide . Silicon oxide is refined by electric arc furnace , Hydrochloric acid chlorination , After distillation , Get high purity 99% Above crystalline silicon . The purity of crystalline silicon is very high , That's why it's expensive to make wafers . Do you know what diamond is ？ Diamond is the element formed by deoxidation of carbon and other factors. The element arrangement is unique and the purity is as high as 99.64% Above the crystal . Think about it , Wafers are much cheaper than artificial diamonds , It's still very cost-effective .
（2） Making crystal rods
Crystalline silicon is formed at high temperature , The round crystal rod is made by rotating and stretching .
（3） Chip segmentation
Cut the crystal bar horizontally into wafers with basically the same thickness ,Wafer
(4) Wafer polishing
Polish the appearance of the wafer
（5）Wafer Coating
Through the heat , Or some other way , Make a layer on the wafer SiO2 silicon dioxide .SiO2 Silicon dioxide is an insulating material , But there are impurities and special treatment SiO2 Silicon dioxide has a little conductivity . here SiO2 The function of silicon dioxide is to conduct light . Just like using SiO2 Silicon dioxide is used as optical waveguide . This is for later lithography .
（6） Apply photoresist
Photoresist is the same as the film used for photography .Wafer Apply photoresist , It is required to be thin and flat .
（7） Photolith （ Extreme violet lithography EVO）
The designed wafer circuit mask , Placed under the ultraviolet light of lithography , Next place Wafer. In the moment of lithography , stay Wafer The photoresist of the lithographic part melts , Engraved with a circuit diagram . Remove photoresist , The pattern on the photoresist should be consistent with the pattern on the mask . Lithography again . The circuit of a wafer needs many times of lithography . With the emergence of new technology of extreme violet lithography , Wafer lithography becomes more accurate , And more efficient , You can even finish all lithography at once .
（8） Ion injection
Through ion injection in vacuum , Inject conductive materials into the lithographic wafer circuit . Generally, ion injection is performed after one lithography . After the second photolithography , Then ion injection . But one full lithography , You can directly conduct ion injection .
（9） electroplate
Basically, the wafer is finished , Next, we need to electroplate a layer of copper sulfate on the wafer . Copper ions will move from positive to negative .
（10） polishing
Polishing Wafer The surface of the , Whole Wafer It has been successfully manufactured .
（11） Wafer slicing
take Wafer Cut into pieces , Single wafer Die
（12） test
There are three main categories ： A functional test 、 Performance testing 、 Anti aging test . The details are as follows ： Contact test 、 Power consumption test 、 Input leakage test 、 Output level test 、 Dynamic parameter test 、 Analog signal parameter test and so on . If there is a bad wafer, it will be scrapped , This is a black piece ; Some tests have not been passed , But those that do not affect the use are divided into white tablets , Can flow out ; And those who pass the test are positive .
（13） Pack in a box
First give Wafer Mulch , Then insert it into the black box .
（14） Send to seal test
Die（ Naked piece ） After sealing and testing , It has become the chip on our electronic digital products .

3.CPU constitute
CPU It's a very large scale integrated circuit , The essence of embedded development is to CPU Operate to realize the corresponding functions .
CPU It's made up of three parts ：

control unit
The control unit is the whole CPU Command and control center , By the instruction register 、 Instruction decoder and operation controller OC(Operation Controller) etc. , It is very important to coordinate the orderly work of the whole computer . It's based on the user's pre programmed program , Take each instruction out of the memory in turn , Put it in the instruction register IR in , By decoding instructions ( analysis ) Determine what to do , And then by operating the controller OC, In a certain sequence , Send micromanipulation control signals to corresponding components . Operating the controller OC It mainly includes beat pulse generator 、 Control matrix 、 Clock generator 、 Reset circuit, start stop circuit and other control logic .

Arithmetic unit
It's the core of the arithmetic unit . Can perform arithmetic operations ( Including addition and subtraction multiplier and other basic operations and additional operations ) And logic ( Including displacement 、 Logic test or comparison of two values ). Relative to the control unit , The arithmetic unit receives the command from the control unit and operates , That is to say, all operations carried out by the operation unit are directed by the control signals sent by the control unit , So it's the executive part .

Storage unit
Include CPU On chip cache and register group , yes CPU Where data is temporarily stored in , It holds the data waiting to be processed , Or data that has been processed ,CPU It takes less time to access registers than to access memory . Use register , Can reduce the CPU Number of memory accesses , So as to improve CPU Working speed of . But because of the limitation of chip area and integration , The capacity of a register group cannot be large . Register group can be divided into special register and general register . The function of special register is fixed , Register the corresponding data separately . General purpose registers are widely used and can be specified by programmers , The number of general purpose registers varies from microprocessor to microprocessor . This is the key point we will introduce later , Let me first mention .

4. The register is CPU An important part of , The function of register is to store binary code , It is composed of triggers with storage function . A trigger can store 1 Bit binary code , Therefore, it should be stored n Bit binary code register , need n A trigger to make up .
Embedded programming requires the configuration of registers , In order to realize the corresponding functions .

Reference link ：
http://m.elecfans.com/article/677109.html
https://www.sohu.com/a/233312100_100180344、http://m.elecfans.com/article/734970.html

author ：sml_tj
link ：https://www.jianshu.com/p/d769a500a05f
source ： Simple books
The copyright belongs to the author . Commercial reprint please contact the author for authorization , Non-commercial reprint please indicate the source .