Regarding PET, here's the little Venn diagram I made up back in 2015 explaining where it is:

PET (Planar Electronic Technology) is neither abandoned nor cancelled nor hidden, it is just part of the full POET (Planar Opto-Electronic Technology), which is a superset of PET. The successful monolithic integration of optical and electronical components or – to be exact – the manufacturing of both on the same epitaxy has been announced last year:

"The specific and significant milestone achieved is the first demonstration of functional Hetero-junction Field Effect Transistors (HFETs) down to 250nm effective gate lengths on the same proprietary epitaxy and utilizing the same integrated process sequence that was previously used to demonstrate high performance detectors."

Here PET takes the shape of the Hetero-junction Field Effect Transistors (HFETs). And in addition you have the 'O' (optics) from the photodetector, forming POET. That is: PET + O = POET.