We describe a silicon nanowire (SiNW) biosensor fabricated in a fully depleted SOI CMOS process. The sensor array consists of N by N pixel matrix (N-2 pixels or test sites) and 8 input-output (I/O) pins. In each pixel a single crystalline SiNW with 75 by 20 nm cross-section area is defined using sidewall transfer lithography in the SOI layer. The key advantage of the design is that each individual SiNWs can be read-out sequentially and used for real-time charge based detection of molecules in liquids or gases. (C) 2014 Elsevier Ltd. All rights reserved.