The comprehensive understanding of the structure-dependent electrostatic discharge behaviors in a conventional diode-triggered silicon controlled rectifier （DTSCR） is presented in this paper. Combined with the devic...The comprehensive understanding of the structure-dependent electrostatic discharge behaviors in a conventional diode-triggered silicon controlled rectifier （DTSCR） is presented in this paper. Combined with the device simulation, a mathematical model is built to get a more in-depth insight into this phenomenon. The theoretical studies are verified by the transmission-line-pulsing （TLP） test results of the modified DTSCR structure, which is realized in a 65-nm complementary metal-oxide-semiconductor （CMOS） process. The detailed analysis of the physical mechanism is used to provide predictions as the DTSCR-based protection scheme is required. In addition, a method is also presented to achieve the tradeoff between the leakage and trigger voltage in DTSCR.展开更多
A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18 μm EEPROM process. The polysilicon-assisted SCRs take advantage of poly...A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18 μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge (ESD) current without occupying extra layout area. TLP current-voltage (I-V) measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of con- ventional MLSCR's. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 μm2 layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.展开更多
This paper presents a new phenomenon,where the holding-voltage of a silicon-controlled rectifier acts as an electrostatic-discharge protection drift in diverse film thicknesses in silicon-on-insulator（SOI） technolog...This paper presents a new phenomenon,where the holding-voltage of a silicon-controlled rectifier acts as an electrostatic-discharge protection drift in diverse film thicknesses in silicon-on-insulator（SOI） technology. The phenomenon was demonstrated through fabricated chips in 0.18μm SOI technology.The drift of the holding voltage was then simulated,and its mechanism is discussed comprehensively through ISE TCAD simulations.展开更多
A diode-triggered silicon controlled rectifier (DTSCR) is being developed as an electrostatic discharge (ESD) pro- tection device for low voltage applications. However, DTSCR leaks high current during normal operation...A diode-triggered silicon controlled rectifier (DTSCR) is being developed as an electrostatic discharge (ESD) pro- tection device for low voltage applications. However, DTSCR leaks high current during normal operation due to the Darlington effect of the triggering-assist diode string. In this study, two types of diode string triggered SCRs are designed for low leakage consideration; the modified diode string and composite polysilicon diode string triggered SCRs (MDTSCR & PDTSCR). Com- pared with the conventional DTSCR (CDTSCR), the MDTSCR has a much lower substrate leakage current with a relatively large silicon cost, and the PDTSCR has a much lower substrate leakage current with similar area and shows good leakage performance at a high temperature. Other DTSCR ESD properties are also investigated, especially regarding their layout, triggering voltage and failure current.展开更多
In order to reduce the latch-up risk of the traditional low-voltage-triggered silicon controlled rectifier(LVTSCR), a novel LVTSCR with embedded clamping diode(DC-LVTSCR) is proposed and verified in a 0.18-μm CMOS pr...In order to reduce the latch-up risk of the traditional low-voltage-triggered silicon controlled rectifier(LVTSCR), a novel LVTSCR with embedded clamping diode(DC-LVTSCR) is proposed and verified in a 0.18-μm CMOS process. By embedding a p+implant region into the drain of NMOS in the traditional LVTSCR, a reversed Zener diode is formed by the p+implant region and the n+bridge, which helps to improve the holding voltage and decrease the snapback region.The physical mechanisms of the LVTSCR and DC-LVTSCR are investigated in detail by transmission line pulse(TLP)tests and TCAD simulations. The TLP test results show that, compared with the traditional LVTSCR, the DC-LVTSCR exhibits a higher holding voltage of 6.2 V due to the embedded clamping diode. By further optimizing a key parameter of the DC-LVTSCR, the holding voltage can be effectively increased to 8.7 V. Therefore, the DC-LVTSCR is a promising ESD protection device for circuits with the operation voltage of 5.5–7 V.展开更多
集成电路中半导体器件的特征尺寸不断减小,集成电路对ESD的冲击更加敏感。静电防护成为集成电路中最重要的可靠性指标之一,ESD保护结构也成为芯片设计中的难题。随着集成电路规模的增大,芯片引脚增多,大量面积被用于ESD保护电路,导致成...集成电路中半导体器件的特征尺寸不断减小,集成电路对ESD的冲击更加敏感。静电防护成为集成电路中最重要的可靠性指标之一,ESD保护结构也成为芯片设计中的难题。随着集成电路规模的增大,芯片引脚增多,大量面积被用于ESD保护电路,导致成本提高。可控硅结构的ESD保护器件相比其他已知保护结构具有最高的单位面积ESD性能,因此成为低成本片上ESD设计方案的首选。针对改进型横向SCR (MLSCR,又称N+桥式SCR)的ESD保护结构,对其关键特性指标结合理论分析与实验数据进行分析。基于某0.18μm 5 V CMOS工艺的流片结果,对SCR结构的工作原理以及关键的触发电压、保持电压参数进行说明,并提出改进方案。展开更多
基金Project supported by the Beijing Municipal Natural Science Foundation,China(Grant No.4162030)the National Science and Technology Major Project of China(Grant No.2013ZX02303002)
文摘The comprehensive understanding of the structure-dependent electrostatic discharge behaviors in a conventional diode-triggered silicon controlled rectifier （DTSCR） is presented in this paper. Combined with the device simulation, a mathematical model is built to get a more in-depth insight into this phenomenon. The theoretical studies are verified by the transmission-line-pulsing （TLP） test results of the modified DTSCR structure, which is realized in a 65-nm complementary metal-oxide-semiconductor （CMOS） process. The detailed analysis of the physical mechanism is used to provide predictions as the DTSCR-based protection scheme is required. In addition, a method is also presented to achieve the tradeoff between the leakage and trigger voltage in DTSCR.
文摘A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18 μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge (ESD) current without occupying extra layout area. TLP current-voltage (I-V) measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of con- ventional MLSCR's. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 μm2 layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.
基金Project supported by the National Natural Science Foundation of China(No.60927006)
文摘This paper presents a new phenomenon,where the holding-voltage of a silicon-controlled rectifier acts as an electrostatic-discharge protection drift in diverse film thicknesses in silicon-on-insulator（SOI） technology. The phenomenon was demonstrated through fabricated chips in 0.18μm SOI technology.The drift of the holding voltage was then simulated,and its mechanism is discussed comprehensively through ISE TCAD simulations.
基金Project partially supported by the Zhejiang Provincial Nature Science Fund of China (Nos. Y107055 and Y1080546)the Semiconductor Manufacturing International Corp. (SMIC)
文摘A diode-triggered silicon controlled rectifier (DTSCR) is being developed as an electrostatic discharge (ESD) pro- tection device for low voltage applications. However, DTSCR leaks high current during normal operation due to the Darlington effect of the triggering-assist diode string. In this study, two types of diode string triggered SCRs are designed for low leakage consideration; the modified diode string and composite polysilicon diode string triggered SCRs (MDTSCR & PDTSCR). Com- pared with the conventional DTSCR (CDTSCR), the MDTSCR has a much lower substrate leakage current with a relatively large silicon cost, and the PDTSCR has a much lower substrate leakage current with similar area and shows good leakage performance at a high temperature. Other DTSCR ESD properties are also investigated, especially regarding their layout, triggering voltage and failure current.
基金National Natural Science Foundation of China(Grant No.61504049)the China Postdoctoral Science Foundation(Grant No.2016M600361).
文摘In order to reduce the latch-up risk of the traditional low-voltage-triggered silicon controlled rectifier(LVTSCR), a novel LVTSCR with embedded clamping diode(DC-LVTSCR) is proposed and verified in a 0.18-μm CMOS process. By embedding a p+implant region into the drain of NMOS in the traditional LVTSCR, a reversed Zener diode is formed by the p+implant region and the n+bridge, which helps to improve the holding voltage and decrease the snapback region.The physical mechanisms of the LVTSCR and DC-LVTSCR are investigated in detail by transmission line pulse(TLP)tests and TCAD simulations. The TLP test results show that, compared with the traditional LVTSCR, the DC-LVTSCR exhibits a higher holding voltage of 6.2 V due to the embedded clamping diode. By further optimizing a key parameter of the DC-LVTSCR, the holding voltage can be effectively increased to 8.7 V. Therefore, the DC-LVTSCR is a promising ESD protection device for circuits with the operation voltage of 5.5–7 V.
文摘集成电路中半导体器件的特征尺寸不断减小,集成电路对ESD的冲击更加敏感。静电防护成为集成电路中最重要的可靠性指标之一,ESD保护结构也成为芯片设计中的难题。随着集成电路规模的增大,芯片引脚增多,大量面积被用于ESD保护电路,导致成本提高。可控硅结构的ESD保护器件相比其他已知保护结构具有最高的单位面积ESD性能,因此成为低成本片上ESD设计方案的首选。针对改进型横向SCR (MLSCR,又称N+桥式SCR)的ESD保护结构,对其关键特性指标结合理论分析与实验数据进行分析。基于某0.18μm 5 V CMOS工艺的流片结果,对SCR结构的工作原理以及关键的触发电压、保持电压参数进行说明,并提出改进方案。
