Since 2017, SSD industry has exposed many problems such as Shanzhai and black core. Many cottage vendors use black solid state hard disk to get more benefits, but consumers don't know what black solid SDS are. So today, I read the meaning of the three nouns of the flash memory particles from the technical level.
First of all, we want to know how the particles in the solid state hard disk come from. Simply speaking, manufacturers who produce wafers produce a complete wafer. The wafer is made of pure silicon (Si), which is generally divided into 6 inches, 8 inches and 12 inches. Wafer is based on wafer production. A small piece of the wafer, a wafer body, called die, is a particle package, is our NandFlash chip in the solid state disk.
The shape of a whole piece of wafer, and the square inside is die.
The wafer is first cut, then tested, and the perfect, stable, full capacity die is removed and encapsulated to form a daily NandFlash chip. Then, the remaining on the wafer is not to be unstable or insufficient, or is partly damaged or completely damaged. The original factory, considering the quality assurance, will announce the death of this die, strictly defined as all waste disposal.
Generally speaking, a wafer is detected, and the qualified die is removed, then it is encapsulated into the flash memory particles in solid state drive, which we call the original film. Then the remaining unqualified die is called black chip. The price of the original film is very high, and the black film as a scrap, the price is very low, the ordinary bad manufacturers to buy black films are all tons of calculation.
So what is the "white film"? In fact, the white film is the original piece of the package after the detection of the defective particles, and then eliminated the garbage. There can be no white in the NAND of the original.
Therefore, black chips and white chips are all bits and pieces produced in the process of chip manufacturing. Black chips are eliminated in the raw material stage, and white chips are defective products after testing. In terms of quality, black chip NAND is very bad, because the original plant has already sentenced it to death penalty, but the downstream plant will sell it after its capacity is reduced, that is, castration, but the quality is still very poor, and the purchase of this particle is also equivalent to gambling.