Making the masks in photoshop is a really neat trick. Reminds me of Bob Moore of Forth fame who said something like "once you have enough code to draw a square you are half way to a chip design package".
I loved this, it made me realise how close to negative development is to photolithography. When doing separate etching layers how are wafers lined up or is everything done in situ?
Interesting. Curious what the yield is. And he doesn't need a cleanroom, or work with dangerous chemicals like HF?
He mentions HF around 4:05 but by that time I have long lost my understanding of whats going on so this may not be what you mean.
I feel this.
I don't think you need a cleanroom if your feature sizes are huge.