A 2.2-mm CMOS Bioassay Chip and Wireless Interface

A biological sensor and wireless interface have been implemented in a 0.25-um RF CMOS process. The device provides a bioassay platform based on an array of CMOS Hall-Effect sensors. The 2.2-mm chip is powered and interrogated by a wireless link and requires no additional packaging for use in biological fluids. Introduction Recently, biological assay platforms based on semiconductor or MEMS technology have been presented [1]. These platforms may include “intelligent” substrates that allow macroscopic laboratory equipment to be integrated into a microscopic environment, often through the use of integrated electronics. By implementing many laboratory functions through large-scale semiconductor manufacturing, these technologies have held promise for low-cost, automated diagnostics for healthcare. However, this potential has been hindered by the requirements of biocompatible packaging, where electrical interfaces must be isolated from fluid samples. So far, these constraints have caused significant increases in chip size and increased manufacturing cost and complexity. Compact chips for RF ID applications have been demonstrated [2], but this technology has not been translated to bioassays. Silicon Wafer Processing