Since 2017, the SSD industry has frequently exposed such issues as the cottage and the black core. Many cottage manufacturers use black-chip SSDs for greater profits, but consumers do not know what the black-chip SSDs are.
So today I from the technical level for everyone to interpret the meaning of the three terms flash memory particles.
Wafer wafer
First, we need to understand how the particles in the SSD come from.
In simple terms, a manufacturer that manufactures a wafer produces a complete wafer, which is made of pure silicon (Si) and is generally divided into 6-inch, 8-inch and 12-inch sizes, The wafer is produced on a wafer basis.
A small piece of wafer, is a wafer wafer body, the scientific name is die, after the package becomes a particle, that is, our Nand Flash chips in the solid state drive.
The shape of an entire wafer, inside the square is die.
The wafer is first cut, then tested, and the intact, stable, full-capacity die is removed and encapsulated to form the daily Nand Flash chip.
Well, the rest of the wafer, either unstable or insufficient capacity, or is partially damaged or completely damaged. The original quality assurance, the die will be declared dead, strictly defined as Waste All scrapped.
In general, a wafer is tested, the die is removed, and then packaged into a solid-state drive in the flash memory particles, which we call the original film, Then the unqualified die, we will call black The price of the original film is very high, while the black film as a scrap, the price is very low, the average bad company to buy black film is calculated as tons.
So what is 'white film'?
In fact, the white film is the original film after the package to detect flaws in the particles, and then eliminated the garbage The genuine NAND can't be white.
Therefore, the black and white chips are actually chips produced in the process of scrap, black film is eliminated in the raw material phase of the part, the white film is finished and then test unqualified defective products.
From a quality point of view, the black film NAND is very bad, because the original factory has been sentenced to death, but the downstream plant to reduce its capacity to sell, that is, castration, but the quality is still very poor, the purchase of such particles Equivalent to gambling.
To this end, it is recommended that users should pay attention to the purchase of solid state drives, like the original product, first of all, they are upstream of the original manufacturers, their own ability to produce and process wafers, monopoly in the Flash raw materials. It is also preferred for stability. After all, SSDs store user data and are not sloppy.
