Chemically-assisted ion-beam etching of (AlGa)As/GaAs: lattice damage and removal by in-situ Cl2 treatment

✍ Scribed by J Daleiden; R Kiefer; S Klußmann; M Kunzer; C Manz; M Wailher; J Braunstein; G Weimann

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 461 KB
• Volume: 45
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(98)00256-1

✦ Synopsis

We evaluated the lattice damage in Al Ga As / GaAs Single Quantum Well (SQW) structures caused by Chemically-0.4 0.6 Assisted Ion-Beam Etching (CAIBE) in comparison with Ion-Beam Etching (IBE) and wet etching. The damage was analyzed by measuring the Photoluminescence (PL) of the SQWs as a function of the etch depth. While IBE (E 5 400 eV) kin causes a damaged region of 27 nm depth, BCl / Cl -CAIBE (E 5 400 eV) damages to a depth of 10 nm. An in-situ 3 2 k i n 24

Cl -treatment (C1 -flow 5 6 sccm, T 5 1208C, p 5 3 3 10 mbar, without plasma) allows a pure chemical removal 2 2 Substrate of the surface layer which was damaged by CAIBE. This combined process facilitates anisotropic etching together with a lattice damage as low as with wet etching.