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Indexed by:期刊论文

Date of Publication:2008-07-01

Journal:MICROELECTRONIC ENGINEERING

Included Journals:SCIE、EI

Volume:85

Issue:7

Page Number:1481-1483

ISSN No.:0167-9317

Key Words:scanning electron microscopy; etching; liquid phase epitaxy; selective epitaxy; semiconducting allium arsenide

Abstract:GaAs pyramidal microtips were successfully transferred from GaAs substrate to target wafer by a simple technique, i.e., selective wet etching off AlGaAs sacrificial layer. A GaAs/Al0.7Ga0.3As/GaAs sandwich structure is firstly formed on GaAs (001) substrate by metalorganic chemical vapor deposition, and then GaAs pyramidal microtips are grown on the sandwich structure using selective liquid-phase epitaxy. The GaAs microtips are removed from the sandwich structure by selective wet etching Al0.7Ga0.3As layer using concentrated HCl solution. Finally, the tips are glued onto the target wafer by a negative photoresist. During this transfer process the tips are completely encapsulated in a positive photoresist to protect against attack. Scanning electron microscopy images show that GaAs tips can be successfully, transferred without any damage by this technique. The achievement reported here represents a significant step towards the application of scanning near-field optical microscopy. (C) 2007 Published by Elsevier B.V.