Breakdown voltage （Vbd） and charge to breakdown （Qbd） are two parameters often used to evaluate gate oxide reliability. In this paper,we investigate the effects of measurement methods on Vbd and Qbd of the gate ox...Breakdown voltage （Vbd） and charge to breakdown （Qbd） are two parameters often used to evaluate gate oxide reliability. In this paper,we investigate the effects of measurement methods on Vbd and Qbd of the gate oxide of a 0.18μm dual gate CMOS process. Voltage ramps （V-ramp） and current ramps （J-ramp） are used to evaluate gate oxide reliability. The thin and thick gate oxides are all evaluated in the accumulation condition. Our experimental results show that the measurement methods affect Vbd only slightly but affect Qbd seriously,as do the measurement conditions.This affects the I-t curves obtained with the J-ramp and V-ramp methods. From the I-t curve,it can be seen that Qbd obtained using a J-ramp is much bigger than that with a V-ramp. At the same time, the Weibull slopes of Qbd are definitely smaller than those of Vbd. This means that Vbd is more reliable than Qbd, Thus we should be careful to use Qbd to evaluate the reliability of 0.18μm or beyond CMOS process gate oxide.展开更多
用斜坡电压法(Voltage Ramp,V-ramp)评价了0·18μm双栅极CMOS工艺栅极氧化膜击穿电量(Charge toBreakdown,Qbd)和击穿电压(Voltage to Breakdown,Vbd).研究结果表明,低压器件(1·8V)的栅极氧化膜(薄氧)p型衬底MOS电容和N型衬...用斜坡电压法(Voltage Ramp,V-ramp)评价了0·18μm双栅极CMOS工艺栅极氧化膜击穿电量(Charge toBreakdown,Qbd)和击穿电压(Voltage to Breakdown,Vbd).研究结果表明,低压器件(1·8V)的栅极氧化膜(薄氧)p型衬底MOS电容和N型衬底电容的击穿电量值相差较小,而高压器件(3·3V)栅极氧化膜(厚氧)p衬底MOS电容和n衬底MOS电容的击穿电量值相差较大,击穿电压测试值也发现与击穿电量相似的现象.其原因可以归结为由于光刻工艺对多晶硅/厚氧界面的损伤.该损伤使多晶硅/厚氧界面产生大量的界面态.从而造成了薄氧与厚氧n衬底和p衬底MOS电容击穿电量差的不同.从Weibull分布来看,击穿电压Weibull分布斜率比击穿电量.击穿电压的分布非常均匀,而且所有样品的失效模式都为本征失效,没有看到“尾巴”,说明工艺非常稳定.展开更多
文摘Breakdown voltage （Vbd） and charge to breakdown （Qbd） are two parameters often used to evaluate gate oxide reliability. In this paper,we investigate the effects of measurement methods on Vbd and Qbd of the gate oxide of a 0.18μm dual gate CMOS process. Voltage ramps （V-ramp） and current ramps （J-ramp） are used to evaluate gate oxide reliability. The thin and thick gate oxides are all evaluated in the accumulation condition. Our experimental results show that the measurement methods affect Vbd only slightly but affect Qbd seriously,as do the measurement conditions.This affects the I-t curves obtained with the J-ramp and V-ramp methods. From the I-t curve,it can be seen that Qbd obtained using a J-ramp is much bigger than that with a V-ramp. At the same time, the Weibull slopes of Qbd are definitely smaller than those of Vbd. This means that Vbd is more reliable than Qbd, Thus we should be careful to use Qbd to evaluate the reliability of 0.18μm or beyond CMOS process gate oxide.
文摘用斜坡电压法(Voltage Ramp,V-ramp)评价了0·18μm双栅极CMOS工艺栅极氧化膜击穿电量(Charge toBreakdown,Qbd)和击穿电压(Voltage to Breakdown,Vbd).研究结果表明,低压器件(1·8V)的栅极氧化膜(薄氧)p型衬底MOS电容和N型衬底电容的击穿电量值相差较小,而高压器件(3·3V)栅极氧化膜(厚氧)p衬底MOS电容和n衬底MOS电容的击穿电量值相差较大,击穿电压测试值也发现与击穿电量相似的现象.其原因可以归结为由于光刻工艺对多晶硅/厚氧界面的损伤.该损伤使多晶硅/厚氧界面产生大量的界面态.从而造成了薄氧与厚氧n衬底和p衬底MOS电容击穿电量差的不同.从Weibull分布来看,击穿电压Weibull分布斜率比击穿电量.击穿电压的分布非常均匀,而且所有样品的失效模式都为本征失效,没有看到“尾巴”,说明工艺非常稳定.
