In Issue 5, 2ooo we looked at the technical and business trends in etch processes for manufacturing gallium arsenide electronic devices. Here we turn to the application of dry etching to fabrication of optoelectronic devices -a much broader area (covering GaAs, lnP as well as GaN and II-Vl materials) to which we will return in later issues. III-Vs REVIEW ~~E ,~)Va2~E~I~ 'SE ~!( ยฉN!"~U(-T~}~; MA~J~Z~ ~. VOL a4 -NO 1 -JAN/FEB 2ooa Etch manufacturers can only share so much technology across both these markets.
Indeed such has been the impetus for MMICs that companies which have chosen to dedicate themselves to this market have -to some extenthad to turn away from opto. Nonetheless, this manufacturing experience should prove invaluable when opto moves to larger wafers. Now that today's compound semiconductor device-processing market is approaching siliconlike scales, a haft-hearted approach is inappropriate. Companies can therefore not spread themselves too thinly, so others have been able to pick up business from the opto market.
However, that too is showing signs of spectacular growth (25% per annum for key components such as LEI)s and lasers).
Recent months have seen many announcements of start-ups and expansions within the opto field.
These will all demand more process tools, of which more will be dry process equipment (such as reactive ion etching and, in particular, inductively-coupled plasma etching). So, too, wet etch processing is having to make way for dry etching. However, even dry processing techniques like ion beam milling and RIE are now having to make way for ICP etching.