Chemical Etching Characteristics of InGaAs / InP and InAlAs / InP Heterostructures

The chemical etching characteristics of (001) MBE and LPE InGaAs and InAlAs layers grown on InP have been studied for various etching systems: H 3 PO 4 : H 2 O 2 , H 2 SO 4 : H 2 O 2 : H 2 O , and Br 2 ‐ CH 3 COOH using photoresist as a mask. The etch profiles were examined on stripes oriented along the [110] and [110] directions and on circular mesa structures. The etch rates and the etch‐revealed planes are reported, together with a detailed discussion of the crystallography. Experimentally observed different etching characteristics between LPE and MBE InGaAs layers are reported and discussed. The use of these etching solutions for device fabrication is also briefly discussed.