Abstract
In this thesis, a novel quasi-vertical insulated gate bipolar transistor (VIGBT) and a quasi-vertical silicon controlled rectifier(VSCR) structure have been designed and fabricated for high voltage ESD protection circuit applications. In addition, a comparison is made among quasi-vertical MOSFETs, quasi-vertical IGBT and quasi-vertical SCR. The device characteristics are simulated using a semiconductor device simulator, MEDICI, to study the effects of device dimensions, then the devices were fabricated in a commercially available 0.5μm 100V process. Devices were then measured and analyzed. Measurement results indicate that, under the same condition, for the devices with 100μm channel width, VIGBT (2Sinker-1Channel)、(1Sikner -2Channel) can handle It2 of 7.22 amps and 9.48 amps. This is larger than It2 of 5.94 amps and 3.18 amps observed in VDMOS(2Sinker- 1Channel)、(1Sinker-2Channel). VIGBT outperforms VDMOS in the aspect of ESD current sustaining capability. For the devices with 200μm channel width, VSCR and VIGBT(1Sinker-2Channel) can handle It2 of 9.58 amps and 9.75 amps. This is larger than It2 of 6.13 amps achieved by VDMOS(1Sinker-2Channel). These results confirm that, due to the parasite PNPN structure, the ESD current sustaining capacity of VSCR and VIGBT is superior than VDMOS.