P Buffer Gallium Arsenide Process for Digital Logic
Original Publication Date: 1982-Dec-01
Included in the Prior Art Database: 2005-Feb-10
Most gallium arsenide digital logic devices are fabricated on semi-insulating gallium arsenide which is neither N-type nor P-type but has a deep acceptor dopant Which compensates for the residual donors in the bulk material. This semi-insulating property simplifies device isolation and since the substrate is neither P-type nor N-type, junction capacitance is at a minimum. Unfortunately, because the dopants, like silicon in the gallium arsenide, have a high dielectric constant, electrical cross coupling can be a problem.