Parasitic isolation transistor having an adjustable threshold voltage

摘要

An method and apparatus for high voltage control of isolation region transistors (320) in an integrated circuit, Isolation region transistors (320) are formed between active devices by selective implantation of channel stop implants (140). Isolation region transistors (320) are those areas with a conductor (130) over an isolation region (120) with no channel stop implant (140). This provides an isolation region transistor (320) with a lower threshold voltage than the areas with channel stop implant (140). The voltage threshold of the isolation region transistors 320 are adjustable to a range of voltages by varying the length of channel stop implant (140). The apparatus may be fabricated using conventional fabrication processes. <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE>