There’s little point in setting up your own semiconductor clean room if you don’t use it practically. Trying to make RAM in response to the RAM crisis can be an interesting goal.
After all, how hard can etching the same structures repeatedly be? [Dr. Semiconductor] details this process in a recent video, leading to actual DRAM creation.
We previously covered the clean room setup, ensuring basic conditions for semiconductor production. The process resembles PCB etching: a photoresist-coated surface is etched using UV through a mask, then into the wafer surface.
With patterns formed, the next step is doping silicon to create active structures, i.e., transistors and capacitors. While ion implantation is the industry standard, the spin-on-glass method was used instead here.
Ultimately, a 5x4 DRAM cell array, not DDR5, was created. Just 20 bits, but the possibility of DIY DRAM is impressive. Scaling up to larger DRAM arrays is planned.
