Etching optical surfaces on GaAs
First Claim
1. A process for fabricating an optical device comprising at least one n-type or intrinsic compound semiconductor consisting of at least 95 mole percent gallium arsenide comprising the step of etching at least part of the compound semiconductor to produce a compound semiconductor surface of optical quality characterized in that the etching procedure is an electrochemical photoetching procedure in which electric current is passed through the compound semiconductor, electrolytic solution with conductivity greater than 0.0001 mhos/cm and anode in which the electrochemical photoetching procedure further comprisesa. applying a potential to the semiconducting compound which is between the maximum potential of the valence band of the semiconductor compound in the electrolytic solution and the minimum potential of the conduction band of the semiconductor compound in the electrolytic solution;
- b. illuminating the part of the surface of the compound semiconductor to be etched with radiation of sufficient energy to produce holes in the valence band; and
c. the electrolytic solution comprises aqueous alkaline solution with pH greater than 11.
1 Assignment
0 Petitions
Accused Products
Abstract
Photoelectrochemical etching of gallium arsenide in highly alkaline aqueous solution yields optically smooth etched surfaces suitable for many optical devices. Higher optical quality is obtained for lower irradiation energy provided sufficient energy is available to produce holes in the valence band.
-
Citations
11 Claims
-
1. A process for fabricating an optical device comprising at least one n-type or intrinsic compound semiconductor consisting of at least 95 mole percent gallium arsenide comprising the step of etching at least part of the compound semiconductor to produce a compound semiconductor surface of optical quality characterized in that the etching procedure is an electrochemical photoetching procedure in which electric current is passed through the compound semiconductor, electrolytic solution with conductivity greater than 0.0001 mhos/cm and anode in which the electrochemical photoetching procedure further comprises
a. applying a potential to the semiconducting compound which is between the maximum potential of the valence band of the semiconductor compound in the electrolytic solution and the minimum potential of the conduction band of the semiconductor compound in the electrolytic solution; -
b. illuminating the part of the surface of the compound semiconductor to be etched with radiation of sufficient energy to produce holes in the valence band; and c. the electrolytic solution comprises aqueous alkaline solution with pH greater than 11. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
Specification