Patent Number: 5,621,227
Date of Patent: April 15, 1997
Inventor: Abhay M. Joshi
Assignee: Discovery Semiconductors, Inc.
A monolithic Optoelectronic Integrated Circuit including a photodiode and a CMOS readout circuit is described in which the diode is formed by compositionally graded layers of InxGa1-xAs selectively epitaxially grown between a substrate of Si and an absorption layer of InxGa1-xAs, the areas of said layers being less than 500 µm2 and wherein a readout circuit on said substrate is coupled to said diode.