Understand everything! Take you to understand the chip "tape out"!

1. What is tape-out?
Tape-out refers to the manufacture of chips on the assembly line through a series of process steps. It is the last link of integrated circuit design, that is, it is sent to manufacture.
Tape-out is "trial production". Simply put, after the circuit is designed, a few or dozens of pieces are produced for testing. If the test passes, mass production will start like this.
Tape-out is the process of turning a circuit design into an ASIC chip. That is, after the Fabless manufacturer has finished designing the circuit, if all inspections and verifications are correct, the final GDSII file will be handed over to the Foundrv factory to produce some sample chips (usually dozens or hundreds of pieces) for inspection. Whether each process step is feasible, and whether the circuit has the required performance and function.

2. How much is a tape-out? Why is it so expensive?
The price of a tape-out is mainly composed of the mask plate and the wafer price, of which the mask plate accounts for a large proportion.
A photomask, also known as a photomask, is a graphic master used in the photolithography process in microelectronics manufacturing. The process of converting the pattern of the mask master to the wafer is like a money printing machine. We can think of a lithography machine as a banknote printing machine. The process of printing the pattern of the banknote master onto paper, just like the lithography machine printing the chip pattern onto the wafer, requires a master. This master is the so-called Mask version.
Manufacturing a chip requires hundreds or even thousands of processes, and the mask is not just one layer. For example, the 14nm process requires about 60 layers, and the 7nm process requires about 80 or more layers. The price of the mask plate mainly depends on the "process node" selected by the chip. The higher the process node, the more expensive the tape-out price. Generally speaking, the more advanced the process node, the more mask layers are required. For example, the tape-out cost of the Kirin 985 using the 7nm EUV process is at least 30 million US dollars. If more mature process technologies such as 16nm or 28nm are used, the tape-out cost will be greatly reduced.
Generally speaking, the 40nm mask is about 5 million, the 28nm mask is about 10 million, and the 14nm mask is about 25 million. (The price of different manufacturers will be different, here is just to show that the cost of MASK is relatively high)
In addition, the overall cost of the mask, including the cost of raw materials such as quartz and photoresist, the cost of using machines such as Mask Writer and Inspection, and the generation of mask-related data, including software authorization such as OPC and MDP, servers Use, and labor development costs and so on. For a chip, a mask plate with dozens of layers requires so many steps, equipment, software, and personnel are indispensable, and it is not surprising that the cost is expensive. There is an introduction to tape-out and IC design positions on the website of Senior Core , so I won’t introduce too much here.
3. The importance of tape-out experience?
It can be said that participating in tape-out is the only way for chip engineers, and it is a rite of passage for chip engineers entering the industry.
For chip engineers, it is considered a complete chip project that includes the tape-out link, and participating in tape-out can also help you learn better in the IC development process.
For example, when making baseband chips, what are the scenarios for low power consumption and what strategies are there for low power consumption, from design to implementation to application level... all of these require support/assistance in the tape-out process. Because you can't just care about the principle, you also need to know what are the uncertain factors in tape-out, and take effective measures to avoid them.
In this way, every time you complete a chip project, you have the opportunity to further set standards for yourself, optimize your workflow, improve work efficiency, and ensure delivery quality.
Especially for commercial chips, tape-out is equivalent to an exam, not only for engineers, but also for companies. Every tape-out is real money, and the number of tape-out failures does not need to be many, and the company can be wiped out once or twice.
For companies with R&D background and financial support, tape-out is also very important. The TOP-level Design House in China wants high-quality delivery and pursues first time right, that is, to make the chip as successful as possible at one time.
There is also a situation where there are hundreds of engineers with super-large chips, and each of them only participates in a small part of it. This kind of students who are not so direct about the sense of participation will also experience a proportional decrease in their feelings.
But, in any case, only filming can turn your ideas and sweat into an actual part of this world, and participating in the actual operation of this world is the first step you should be proud of anyway.
4. How long does it take to tape out?
The tape-out process usually takes 3-6 months (including raw material preparation, photolithography, doping, electroplating, packaging and testing), which is the most important and most expensive link in chip manufacturing. However, the specific situation of tape-out depends on the production capacity of chip tape-out manufacturers.
After the tape-out process, it will transition to the mass production stage, where the chip mass production level test will be carried out, and the software in the chip will also be developed at the same time, and finally mass production will be carried out.