That is fine. Nothing wrong with ignorance. Each of us is ignorant about many things. The issue is whether we admit it or not. The important thing for you to know about the PDF Chinese is that they are openly contemptuous of knowledge and experience. They genuinely believe they do not need to know/experience to blab about anything.
Anyway...I am currently in the semicon manufacturing industry, specifically at the Probe step of the entire process.
The probe step, or Probe Functional/Parametric Dept, is where the semicon wafer is actually tested for their functionality, whether it is DRAM, NOR, NAND, SRAM, and many other designs. My job is in process engineering, meaning I make sure the wafer move out of the fab and into the customer's hands with no issues. I make sure Production move the product efficiently, the Functional/Parametric engineers codes works, and the final disposition of each wafer is correct. In other words, I have to know a little bit of everyone else's jobs.
Intel, Samsung, Hynix, Micron, just a few large names, have fabs in mainland China, as well as outside of China. Every step from wafer start to die extraction. Some fabs maybe too small to have the complete process flow, and usually extraction, or Back End (BE), is offloaded to another facility. There are Chinese fabs that are contract fabs or foundries. They usually work from someone else's designs, such as Apple who design the chip but do not have the mass volume capability, so Apple contract that volume production out.
In reference to my post 24...
Each fab is treated uniquely by all customers, meaning that just because SMIC Fab 1 make the standard 64gb NAND wafers, that does not mean Fab 2 can produce the same without passing engineering qualifications tests by the customers. A new fab is treated with the same suspicion and it is industry practice. Depending on the product, a wafer can take up to four months to make it to Probe. Then the customer will do their own testing on the dies they extracted. Then they will literally scrap all those wafers/dies and wait for the next engineering batch. They will do that until a batch of wafers passed their tests. Then once the customer approved, the process is locked down, and wafers from this approved process can be made into consumer level products, whether it is an SD card or memory module for a smart refrigerator or fuel controller for the car, whatever it is. If the process is changed, such as a new wafer processing hardware, the customers must be notified, and the entire aforementioned qualification process starts anew. Depending on the product, the qualification process can take up to two yrs.
As a side note, for several yrs I pointed that out and not one of the PDF Chinese have dared to challenge what I said because they know that I am the real deal and they are frauds. I have debunked many of their claims about the semicon industry.
As far as these latest moves by the US, the resignations of so many engineers
WILL worry customers. The resignations are the equivalent of a major process change, and if a fab have enough engineers who quit, the entire fab will be downgraded to 'engineering qualification' status. No customer will take a chance. It does not matter if the final product is a smart refrigerator. If a flawed die from an unqualified fab made it into that smart refrigerator, or more serious like an automated pump in an oil pipeline, the failure could be catastrophic costing the customer money or even lives. ISO and customers routinely audit fabs and they do it independently of each other. If Panasonic find unacceptable particle count in an deposition chamber, Panasonic can decert the entire fab. Other customers can still buy and use products from that fab, but usually, if one major customer decert a fab, others will follow.
So do not trust what the PDF Chinese say about China's semicon industry. They are not here to educate and inform, but to outright lie and mislead.
