A novel pH sensitive ISFET with on chip temperature sensing using CMOS standard process

A monolithic chip processing method is reported, which includes the ion sen sitive field effect transistor (ISFET) of the pH sensor, p-n diode of tempe rature sensor and readout circuit using 0.5 mum double poly double metal (D PDM) standard CMOS product with UMC IC foundry company. We have designed a planar diffused silicon diode on a n-channel pH sensitive ISFET sensor to a ct as a temperature sensor for on-chip temperature measurement and compensa tion. Furthermore, the device integrated the dual sensors and readout circu it has the potential advantages of achieving, both the pH and temperature v alue display, with this process, ISFET's temperature coefficient can be min imized. (C) 2001 Elsevier Science B.V. All rights reserved.