I'd like your thoughts on something...do you believe the Digitimes report that TSMC's 20nm is yielding at only 20-30%, or are they wrong? Can you tell us what the yield improvement curve for 28nm looked like?
Also, could you tell me if Samsung actually builds its own process tech, or if it simply licenses/tweaks the process from the Common Platform Alliance (i.e. "IBM Fab Club")? I remember a former TI engineer telling me that Samsung is part of this "club" but that it still goes off and does its own thing.
TSMC does not have one yield number since they have diverse products at 20nm. FPGAs, SoCs, GPUs, yield numbers are legally protected but what I can say is that 20nm is exceeding expectations. My bet is still that 20nm will start the revenue ramp in Q1 2014.
I will be at the TSMC OIP Forum on Tuesday and will know more then. TSMC's top customers will be there, people who I know and trust, that is where the cleanest info comes from.
Samsung builds its own fabs but does license process technology from IBM. Same for GF, UMC, and SMIC. Samsung definitely does tweak the process as does GF. SMIC and UMC not so much.