This paper presents a new technique for modeling High-Voltage lightly-doped-drain MOS (HV MOS) devices accurately with the BSIM3v3 SPICE model. Standard SPICE models do not model the voltage dependency of Rs and Rd in HV MOS devices; this causes large discrepancies between the simulated and measured I-V characteristics of HV MOS devices. We propose to assign physical meanings and values different from the original BSIM3v3 model to three of its parameters to represent the voltage dependency of Rs and Rd. With this method, we have succeeded in highly accurate parameter extraction, and the simulated I-V characteristics of HV MOS devices using the extracted parameters match the measured results well. The relationship between the proposed modeling technique and the physical mechanism of HV MOS devices is also discussed based on measurement and device simulation results. Since our method does not change any model equations of BSIM3v3, it can be applied to any SPICE simulator on which the BSIM3v3 model runs, so we can use SPICE simulation for accurate circuit design of complex circuits using HV MOS devices.

This paper presents a new technique for accurately modeling uni-directional High-Voltage lightly-doped- drain MOS (HV MOS) devices by extending the bi- directional HV MOS model and adopting a new parameter extraction method. We have already reported on a SPICE model for bi-directional HV MOS devices based on BSIM3v3. However, if we apply this bi- directional HV MOS model and its parameter extraction technique directly to uni-directional HV MOS devices, there are large discrepancies between the measured and simulated I-V characteristics of the uni- directional devices. This paper extends the bi- directional HV MOS model, and adopts a new parameter extraction technique. Using parameters extracted with the new method, the simulated I-V characteristics of the uni-directional n-channel HV MOS device match the measured results well. Since our method does not change any model equations of BSIM3v3, it can be applied to any SPICE simulator on which the BSIM3v3 model runs.