This paper proposes an oxide filled extended trench gate super junction （SJ） MOSFET structure to meet the need of higher frequency power switches application. Compared with the conventional trench gate SJ MOSFET, ne...This paper proposes an oxide filled extended trench gate super junction （SJ） MOSFET structure to meet the need of higher frequency power switches application. Compared with the conventional trench gate SJ MOSFET, new structure has the smaller input and output capacitances, and the remarkable improvements in the breakdown voltage, on-resistance and switching speed. Furthermore, the SJ in the new structure can be realized by the existing trench etching and shallow angle implantation, which offers more freedom to SJ MOSFET device design and fabrication.展开更多
A low specific on-resistance （RS,on） silicon-on-insulator （SOI） trench MOSFET （nmtal-oxide-semiconductor-field- effect-transistor） with a reduced cell pitch is proposed. The lateral MOSFET features multiple tren...A low specific on-resistance （RS,on） silicon-on-insulator （SOI） trench MOSFET （nmtal-oxide-semiconductor-field- effect-transistor） with a reduced cell pitch is proposed. The lateral MOSFET features multiple trenches： two oxide trenches in the drift region and a trench gate extended to the buried oxide （BOX） （SOI MT MOSFET）. Firstly, the oxide trenches increase the average electric field strength along the x direction due to lower permittivity of oxide compared with that of Si; secondly, the oxide trenches cause multiple=directional depletion, which improves the electric field distribution and enhances the reduced surface field （RESURF） effect in the SOI layer. Both of them result in a high breakdown voltage （BV）. Thirdly, the oxide trenches cause the drift region to be folded in the vertical direction, leading to a shortened cell pitch and a reduced Rs,on. Fourthly, the trench gate extended to the BOX further reduces RS,on, owing to the electron accumulation layer. The BV of the MT MOSFET increases from 309 V for a conventional SOI lateral double diffused metal-oxide semiconductor （LDMOS） to 632 V at the same half cell pitch of 21.5 μm, and RS,on decreases from 419 mΩ cm2 to 36.6 mΩ. cm2. The proposed structure can also help to dramatically reduce the cell pitch at the same breakdown voltage.展开更多
An integrable silicon-on-insulator （SOl） power lateral MOSFET with a trench gate and a recessed drain （TGRD MOSFET） is proposed to reduce the on-resistance. Both of the trench gate extended to the buried oxide （...An integrable silicon-on-insulator （SOl） power lateral MOSFET with a trench gate and a recessed drain （TGRD MOSFET） is proposed to reduce the on-resistance. Both of the trench gate extended to the buried oxide （BOX） and the recessed drain reduce the specific on-resistance （Ron, sp） by widening the vertical conduction area and shortening the extra current path. The trench gate is extended as a field plate improves the electric field distribution. Breakdown voltage （BV） of 97 V and Ron, sp of 0.985 mf2-cm2 （l/os = 5 V） are obtained for a TGRD MOSFET with 6.5/xm half-cell pitch. Compared with the trench gate SOI MOSFET （TG MOSFET） and the conventional MOSFET, Ron＇ sp of the TGRD MOSFET decreases by 46% and 83% at the same BV, respectively. Compared with the SOI MOSFET with a trench gate and a trench drain （TGTD MOSFET）, BV of the TGRD MOSFET increases by 37% at the same Ron,sp.展开更多
An improved breakdown voltage （BV） SOI power MOSFET with a reduced cell pitch is proposed and fabricated. Its breakdown characteristics are investigated numerically and experimentally. The MOSFET features dual trenc...An improved breakdown voltage （BV） SOI power MOSFET with a reduced cell pitch is proposed and fabricated. Its breakdown characteristics are investigated numerically and experimentally. The MOSFET features dual trenches （DTMOS）, an oxide trench between the source and drain regions, and a trench gate extended to the buried oxide （BOX）. The proposed device has three merits. First, the oxide trench increases the electric field strength in the x-direction due to the lower permittivity of oxide （eox） than that of Si （esi）. Furthermore, the trench gate, the oxide trench, and the BOX cause multi-directional depletion, improving the electric field distribution and enhancing the RESURF （reduced surface field） effect. Both increase the BV. Second, the oxide trench folds the drift region along the y-direction and thus reduces the cell pitch. Third, the trench gate not only reduces the on-resistance, but also acts as a field plate to improve the BV. Additionally, the trench gate achieves the isolation between high-voltage devices and the low voltage CMOS devices in a high-voltage integrated circuit （HVIC）, effectively saving the chip area and simplifying the isolation process. An 180 V prototype DTMOS with its applied drive IC is fabricated to verify the mechanism.展开更多
An ultra-low specific on-resistance trench gate vertical double-diffused metal-oxide semiconductor with a high-k dielectric-filled extended trench（HK TG VDMOS） is proposed in this paper.The HK TG VDMOS features a hi...An ultra-low specific on-resistance trench gate vertical double-diffused metal-oxide semiconductor with a high-k dielectric-filled extended trench（HK TG VDMOS） is proposed in this paper.The HK TG VDMOS features a high-k（HK） trench below the trench gate.Firstly,the extended HK trench not only causes an assistant depletion of the n-drift region,but also optimizes the electric field,which therefore reduces Ron,sp and increases the breakdown voltage（BV）.Secondly,the extended HK trench weakens the sensitivity of BV to the n-drift doping concentration.Thirdly,compared with the superjunction（SJ） vertical double-diffused metal-oxide semiconductor（VDMOS）,the new device is simplified in fabrication by etching and filling the extended trench.The HK TG VDMOS with BV = 172 V and Ron,sp = 0.85 mΩ·cm2 is obtained by simulation;its Ron,sp is reduced by 67% and 40% and its BV is increased by about 15% and 5%,in comparison with those of the conventional trench gate VDMOS（TG VDMOS） and conventional superjunction trench gate VDMOS（SJ TG CDMOS）.展开更多
基金supported by the Doctor Scientific Research Start-up Foundation of Xi'an University of Technology of China
文摘This paper proposes an oxide filled extended trench gate super junction （SJ） MOSFET structure to meet the need of higher frequency power switches application. Compared with the conventional trench gate SJ MOSFET, new structure has the smaller input and output capacitances, and the remarkable improvements in the breakdown voltage, on-resistance and switching speed. Furthermore, the SJ in the new structure can be realized by the existing trench etching and shallow angle implantation, which offers more freedom to SJ MOSFET device design and fabrication.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60806025 and 60976060)the Science Fund of the National Laboratory of Analog Integrated Circuit (Grant No. 9140C0903070904)the Innovation Foundation of the State Key Laboratory of Electronic Thin Films and Integrated Devices (Grant No. CXJJ201004)
文摘A low specific on-resistance （RS,on） silicon-on-insulator （SOI） trench MOSFET （nmtal-oxide-semiconductor-field- effect-transistor） with a reduced cell pitch is proposed. The lateral MOSFET features multiple trenches： two oxide trenches in the drift region and a trench gate extended to the buried oxide （BOX） （SOI MT MOSFET）. Firstly, the oxide trenches increase the average electric field strength along the x direction due to lower permittivity of oxide compared with that of Si; secondly, the oxide trenches cause multiple=directional depletion, which improves the electric field distribution and enhances the reduced surface field （RESURF） effect in the SOI layer. Both of them result in a high breakdown voltage （BV）. Thirdly, the oxide trenches cause the drift region to be folded in the vertical direction, leading to a shortened cell pitch and a reduced Rs,on. Fourthly, the trench gate extended to the BOX further reduces RS,on, owing to the electron accumulation layer. The BV of the MT MOSFET increases from 309 V for a conventional SOI lateral double diffused metal-oxide semiconductor （LDMOS） to 632 V at the same half cell pitch of 21.5 μm, and RS,on decreases from 419 mΩ cm2 to 36.6 mΩ. cm2. The proposed structure can also help to dramatically reduce the cell pitch at the same breakdown voltage.
基金supported by the National Natural Science Foundation of China(Nos.60976060,61176069)the National Key Laboratory of AnalogIntegrated Circuit(NLAIC),China(No.9140C090304110C0905)the State Key Laboratory of Electronic Thin Films and Integrated Devices,China(No.CXJJ201004)
文摘An integrable silicon-on-insulator （SOl） power lateral MOSFET with a trench gate and a recessed drain （TGRD MOSFET） is proposed to reduce the on-resistance. Both of the trench gate extended to the buried oxide （BOX） and the recessed drain reduce the specific on-resistance （Ron, sp） by widening the vertical conduction area and shortening the extra current path. The trench gate is extended as a field plate improves the electric field distribution. Breakdown voltage （BV） of 97 V and Ron, sp of 0.985 mf2-cm2 （l/os = 5 V） are obtained for a TGRD MOSFET with 6.5/xm half-cell pitch. Compared with the trench gate SOI MOSFET （TG MOSFET） and the conventional MOSFET, Ron＇ sp of the TGRD MOSFET decreases by 46% and 83% at the same BV, respectively. Compared with the SOI MOSFET with a trench gate and a trench drain （TGTD MOSFET）, BV of the TGRD MOSFET increases by 37% at the same Ron,sp.
基金Projects supported by the National Natural Science Foundation of China(No.61176069)the Special Financial Gnants from the China Postdoctoral Science Foundation and Chongqing(Nos.2012T50771,XM2012004)
文摘An improved breakdown voltage （BV） SOI power MOSFET with a reduced cell pitch is proposed and fabricated. Its breakdown characteristics are investigated numerically and experimentally. The MOSFET features dual trenches （DTMOS）, an oxide trench between the source and drain regions, and a trench gate extended to the buried oxide （BOX）. The proposed device has three merits. First, the oxide trench increases the electric field strength in the x-direction due to the lower permittivity of oxide （eox） than that of Si （esi）. Furthermore, the trench gate, the oxide trench, and the BOX cause multi-directional depletion, improving the electric field distribution and enhancing the RESURF （reduced surface field） effect. Both increase the BV. Second, the oxide trench folds the drift region along the y-direction and thus reduces the cell pitch. Third, the trench gate not only reduces the on-resistance, but also acts as a field plate to improve the BV. Additionally, the trench gate achieves the isolation between high-voltage devices and the low voltage CMOS devices in a high-voltage integrated circuit （HVIC）, effectively saving the chip area and simplifying the isolation process. An 180 V prototype DTMOS with its applied drive IC is fabricated to verify the mechanism.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60806025 and 61176069 )the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-11-0062)
文摘An ultra-low specific on-resistance trench gate vertical double-diffused metal-oxide semiconductor with a high-k dielectric-filled extended trench（HK TG VDMOS） is proposed in this paper.The HK TG VDMOS features a high-k（HK） trench below the trench gate.Firstly,the extended HK trench not only causes an assistant depletion of the n-drift region,but also optimizes the electric field,which therefore reduces Ron,sp and increases the breakdown voltage（BV）.Secondly,the extended HK trench weakens the sensitivity of BV to the n-drift doping concentration.Thirdly,compared with the superjunction（SJ） vertical double-diffused metal-oxide semiconductor（VDMOS）,the new device is simplified in fabrication by etching and filling the extended trench.The HK TG VDMOS with BV = 172 V and Ron,sp = 0.85 mΩ·cm2 is obtained by simulation;its Ron,sp is reduced by 67% and 40% and its BV is increased by about 15% and 5%,in comparison with those of the conventional trench gate VDMOS（TG VDMOS） and conventional superjunction trench gate VDMOS（SJ TG CDMOS）.
