Open AccessEffective improvement in the etching characteristics of Si{110} in low concentration TMAH solution
Author(s) -
Swarnalatha Veerla,
Narasimha Rao Avvaru Venkata,
Pal Prem
Publication year - 2018
Publication title -
micro and nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.25
H-Index - 31
ISSN - 1750-0443
DOI - 10.1049/mnl.2017.0610
Subject(s) - etching (microfabrication) , materials science , tetramethylammonium hydroxide , surface micromachining , bulk micromachining , silicon , fabrication , microstructure , wafer , microelectromechanical systems , reactive ion etching , dry etching , nanotechnology , chemical engineering , composite material , optoelectronics , layer (electronics) , engineering , medicine , alternative medicine , pathology
An aqueous tetramethylammonium hydroxide (TMAH) solution is widely used for silicon wet anisotropic etching to perform bulk micromachining for the fabrication of microstructures on a silicon wafer. To reduce the etching time to increase the productivity, etchant must provide high etch rate. In the present work, the etching characteristics of Si{110} in low concentration TMAH (5 wt%) with the addition of various concentrations (5–20%) of reducing agent hydroxylamine (NH 2 OH) have been studied to increase the etch rate of Si{110} to reduce the etch time for the fabrication of microstructures. Moreover, it is aimed to enhance the undercutting at convex corner for the fast release of the structure. The etch rate of Si{110} and the undercutting at convex corners with the addition of NH 2 OH increases by more than three times that in pure TMAH. In addition to the etch rate and undercutting, the effect of NH 2 OH on etched surface morphology is investigated systematically. The present study is focused to enhance the application of wet etching in silicon micromachining for the fabrication of various kinds of microstructures for applications in microelectromechanical systems.