US Patent 7247877 - Integrated circuit monitor using CNTFET

http://www.freepatentsonline.com/7247877.html

Several integrated circuit designs include monitoring circuits built into the chip to assure proper functioning of the circuit. However, the space taken up by these circuits can increase the size of the chips and reduce overall performance. This patent from IBM teaches the use of carbon nanotube field effect transistors to detect defective transistors with a greater economy of space.

1. An integrated circuit comprising: a primary transistor device to be monitored; and an embedded carbon nanotube field effect transistor (CNT FET) spaced apart from said primary transistor device to be monitored, wherein said CNT FET is adapted to detect defective circuits and measure physical characteristics within said integrated circuit, wherein said CNT FET is adapted to measure any of mechanical and thermal stress and strain in said integrated circuit, and wherein said primary transistor device to be monitored comprises: a gate; a source region; a drain region; and a gate insulator layer separating said gate from each of said source region and said drain region.