How are SSDs Made?

Micron manufactures solid state drives from the ground up. Every step of the process is handled in-house, from creating flash media out of silicon wafers to building printed circuit boards to assembling the finished products. We then test the products rigorously for quality and reliability before shipping them to customers all over the world.

Solid state drives use flash memory chips to store information, an SSD is made of several memory chips installed on a circuit board. Micron manufactures the flash memory chips in‑house on silicon wafers, similar to how Micron makes its computer memory. 

Because the silicon wafers are susceptible to contamination, robots move the wafers through more than 800 operations, which take more than a month to complete. As the wafers move through the process, many layers of materials are added to the wafer. These include conductive materials such as copper and non-conductive materials like silicone dioxide. After each layer of material is applied, the wafer is coated with light-sensitive fluid, then ultraviolet light is flashed on to it through a glass stencil of the electrical circuitry pattern. Where the light contacts the materials, they break down and dissolve. Where the materials are shielded by the stencil, they remain intact, which prints the circuitry pattern on the wafer. Chemical baths then wash away any residual material.

After printing, each 30-centimeter wafer yields hundreds of chips, which must be sliced apart. After the chips are cut apart, they are inserted into a protective plastic housing. 

Large circuit boards are covered with tin alloy solder paste in the areas the memory chips and other components will be attached. A robot attaches the components to the board, then the assembled boards go into an oven that fuses the components to the board.

The boards first go through an optical scan to verify that the components on the board are in the correct place, then the next machine x-rays the board to ensure that everything is soldered in the correct place. The large circuit boards are now cut into individual boards and, in the case of a 2.5-inch drive, inserted into plastic housing.

Every drive is then labeled with its model and serial numbers, technical specifications, and other information. One other piece of information is a bar code for production tracking. The drives are plugged into a tester to verify functionality and install the firmware that runs the drive. The drive then undergoes up to 60 hours of performance testing to ensure that it stores data correctly and reads and writes at target speeds. Micron's SSDs are also tested with a variety of motherboards to ensure widespread compatibility.

The drives are then packaged with a foil pouch to avoid static electricity, and placed in a carton. From there, they are sent anywhere in the world.

Micron is one of the few manufacturers that makes solid state drives from the silicon up. With quality control from the first step to the last, the drives are guaranteed, and with the Crucial® Advisor™ tool or System Scanner tool, you can find the right form factor, the right interface, and the right size for your storage needs.