New High Frequency Model For Substrate Crosstalk Noise Injected By SOI Devices

Silicon on insulator (SOI) device and circuits are used for decreasing the amount of noise, which transmits from one device to others on the same chip. While an SOI based process provides high isolation from crosstalk at low operating frequencies, its benefits are lost at high frequencies. In this paper the mechanisms, which cause production of substrate noise in CMOS devices, are discussed and compared between bulk and SOI devices. It was shown that, increasing the amount of impact ionization current is the main reason for substrate noise degradation in high frequency SOI circuits compared with bulk devices. In this paper, a new model is introduced for analyzing substrate noise in high frequency SOI devices, by considering impact ionization currents