Since many potential MEMS devices may involve contact between sidewalls, studying stiction between sidewalls can be critical to the commercial success of MEMS. However, to date, only a few microinstruments dedicated to investigate sidewall stiction have been reported and even they posses several limitations. Therefore, in this paper, we report on an improved microinstrument to study sidewall stiction, which not only addresses some of the limitations of other microinstruments but is also easy to fabricate. The design, fabrication and modeling of the microinstrument are described in the paper. The paper also reports the apparent work of adhesion of octadecyltrichloro-silane (OTS) coated sidewall surfaces as well as sidewall surfaces with only native oxide on them. (C) 2011 Elsevier B.V. All rights reserved.