A uniform doping ultra-thin silicon-on-insulator(SOI) lateral-double-diffused metal-oxide-semiconductor(LDMOS)with low specific on-resistance(R_on,sp) and high breakdown voltage(BV) is proposed and its mechani...A uniform doping ultra-thin silicon-on-insulator(SOI) lateral-double-diffused metal-oxide-semiconductor(LDMOS)with low specific on-resistance(R_on,sp) and high breakdown voltage(BV) is proposed and its mechanism is investigated.The proposed LDMOS features an accumulation-mode extended gate(AG) and back-side etching(BE). The extended gate consists of a P– region and two diodes in series. In the on-state with VGD〉 0, an electron accumulation layer is formed along the drift region surface under the AG. It provides an ultra-low resistance current path along the whole drift region surface and thus the novel device obtains a low temperature distribution. The R_on,sp is nearly independent of the doping concentration of the drift region. In the off-state, the AG not only modulates the surface electric field distribution and improves the BV, but also brings in a charge compensation effect to further reduce the R_on,sp. Moreover, the BE avoids vertical premature breakdown to obtain high BV and allows a uniform doping in the drift region, which avoids the variable lateral doping(VLD) and the "hot-spot" caused by the VLD. Compared with the VLD SOI LDMOS, the proposed device simultaneously reduces the R_on,sp by 70.2% and increases the BV from 776 V to 818 V.展开更多
The automatic platform gates system (APG) and platform screen doors system (PSD) have been applied in the subways in some cities because of its security. As for the two methods,sometimes,it is difficult to decide whic...The automatic platform gates system (APG) and platform screen doors system (PSD) have been applied in the subways in some cities because of its security. As for the two methods,sometimes,it is difficult to decide which one is better for a certain project. The influence of the train-induced air on subway station and the comfort level of subway station in dynamic and transient conditions was analysized based on experimental data. The comfort level,content of inspiratory particles and noise level show that the environment of subway station with APG can satisfy the requirement of the standard. The air conditioning (A/C) cooling load and ventilation energy consumption of the two kinds of subway stations was predicted with the EnergyPlus program. Because electricity consumption by ventilation equipment increases notably when PSD is used,particularly the electricity consumption by the under platform exhaust (UPE) fan,and thus,ultimately,little difference exists in the overall energy consumption with and without PSD. The APG system is economical for the subway stations of the north cities. And it can satisfy the comfort of passengers for whistle stop. It can be concluded that in north cities APG system is better than PSD system.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61176069 and 61376079)
文摘A uniform doping ultra-thin silicon-on-insulator(SOI) lateral-double-diffused metal-oxide-semiconductor(LDMOS)with low specific on-resistance(R_on,sp) and high breakdown voltage(BV) is proposed and its mechanism is investigated.The proposed LDMOS features an accumulation-mode extended gate(AG) and back-side etching(BE). The extended gate consists of a P– region and two diodes in series. In the on-state with VGD〉 0, an electron accumulation layer is formed along the drift region surface under the AG. It provides an ultra-low resistance current path along the whole drift region surface and thus the novel device obtains a low temperature distribution. The R_on,sp is nearly independent of the doping concentration of the drift region. In the off-state, the AG not only modulates the surface electric field distribution and improves the BV, but also brings in a charge compensation effect to further reduce the R_on,sp. Moreover, the BE avoids vertical premature breakdown to obtain high BV and allows a uniform doping in the drift region, which avoids the variable lateral doping(VLD) and the "hot-spot" caused by the VLD. Compared with the VLD SOI LDMOS, the proposed device simultaneously reduces the R_on,sp by 70.2% and increases the BV from 776 V to 818 V.
基金Project(033112911) supported by Tiangjin Science and Technology Committee,China
文摘The automatic platform gates system (APG) and platform screen doors system (PSD) have been applied in the subways in some cities because of its security. As for the two methods,sometimes,it is difficult to decide which one is better for a certain project. The influence of the train-induced air on subway station and the comfort level of subway station in dynamic and transient conditions was analysized based on experimental data. The comfort level,content of inspiratory particles and noise level show that the environment of subway station with APG can satisfy the requirement of the standard. The air conditioning (A/C) cooling load and ventilation energy consumption of the two kinds of subway stations was predicted with the EnergyPlus program. Because electricity consumption by ventilation equipment increases notably when PSD is used,particularly the electricity consumption by the under platform exhaust (UPE) fan,and thus,ultimately,little difference exists in the overall energy consumption with and without PSD. The APG system is economical for the subway stations of the north cities. And it can satisfy the comfort of passengers for whistle stop. It can be concluded that in north cities APG system is better than PSD system.