Wet chemical etch solutions for Al{sub x}Ga{sub 1{minus}x}P
- Univ. of Florida, Gainesville, FL (United States). Dept. of Materials Science and Engineering
- AT and T Bell Labs., Murray Hill, NJ (United States)
Heterostructures based on AlGaInP alloy compounds are very attractive for visible semiconductor lasers, heterojunction bipolar transistors (HBTs), and high-electron-mobility transistors (HEMTs) lattice matched to GaAs substrates. Several wet etching solutions for AlGaP of different compositions have been studied. Al{sub 0.5}Ga{sub 0.5}P is found to etch in HF, H{sub 3}PO{sub 4}, hyphosphorous acid (HOPH{sub 2}:O), HCl, KOH, and 1% Br{sub 2}-methanol (MeOH). Etching of Al{sub 0.5}Ga{sub 0.5}P in HCl is reaction limited with an activation energy of {approximately}54.4 kJ/mol. At fixed conditions, the etch rates of Al{sub x}Ga{sub 1{minus}x}P vary exponentially with x in HF and HCl, while in 1% Br{sub 2}-MeOH and mixtures of HCl and HNO{sub 3} the etch rates follow a linear dependence on AlP mole fraction. HF has been found to be a good etchant for AlGaP over InGaP or AlInP with high selectivity, while HCl is useful for the reverse case. The use of 1% Br{sub 2}-MeOH or the mixtures of HCl and HNO{sub 3} provides little selectivity between AlGaP, InGaP, AlInP, and GaAs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 201378
- Journal Information:
- Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 1 Vol. 143; ISSN 0013-4651; ISSN JESOAN
- Country of Publication:
- United States
- Language:
- English
Similar Records
High ion density plasma etching of InGaP, AlInP, and AlGaP in CH{sub 4}/H{sub 2}/Ar
Fabrication of novel III-N and III-V modulator structures by ECR plasma etching