For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the ...For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the conventional single channel. Then the n-drift concentration can be increased to decrease the Kirk effect, while keeping off-state breakdown voltage Vbd unchanged. Meanwhile the influence of the n-drift concentration and the n-drift length Ldrift （the drain n＋ diffusion to gate spacing） which are related to the Kirk effect is discussed. The trade-offs between Rdson.Area, breakdown voltage Vbd and the electrical safe operating area （e-SOA） performance of LDMOS are considered also. Finally the proposed planar active-gap LDMOS devices with varied values of Ldria are experimentally demonstrated. The experimental results show that the Kirk effect can be greatly suppressed with slight increase in the Rdson.Area parameter.展开更多
为了更精确预测基于0.18μm工艺的40 V NLDMOS器件实际应用条件下的热载流子寿命,介绍了一种通过可靠性测试和计算机辅助数学解析相结合的热载流子可靠性寿命预计方法。该方法基于实际直流状态下的热载流注入测试数据,结合TCAD仿真,对...为了更精确预测基于0.18μm工艺的40 V NLDMOS器件实际应用条件下的热载流子寿命,介绍了一种通过可靠性测试和计算机辅助数学解析相结合的热载流子可靠性寿命预计方法。该方法基于实际直流状态下的热载流注入测试数据,结合TCAD仿真,对测试结果进行了线性函数、多次函数、幂函数、指数函数及Dreesen R函数拟合;通过分析当前业界LDMOS器件的热载流子注入测试主流模型预测精度的局限性,找出了最优热载流子模型,提出了适合Python语言编程的改进型Dreesen R模型;通过数学解析推导方法以及基于Python语言的计算机辅助编程计算,得出了栅极以及漏极全工作电压范围内的热载流子参数退化曲线;通过模拟工作波形不同上升沿及下降沿的函数曲线、上升及下降时间以及不同占空比,得出随着时间变化的交直流转换因子曲线。最终新的测试项目可以通过不同电压下的直流状态下测试结果以及已经得到的交直流转换因子曲线,来直接获取工作场景交流状态的热载流子寿命。该评估方法解决了采用直流状态下的测试来解决现场复杂应用波形的热载流子寿命评估难题,较大节省了测试时间,提高了寿命预测精度。展开更多
Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a the...Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a thermionic-field-diffusion model that is used to the analyze the performance of an abrupt HBT with a heavydoped base, the conclusion is made that, although the BGN effect makes the currents obviously change due to the modification of the intrinsic carrier density, the band offsets disturbed by the BGN effect should also be taken into account in the analysis of the electrical characteristics of abrupt HBTs. In addition, the BGN effect changes the bias voltage for the onset of Kirk effects.展开更多
文摘For 20 V planar active-gap lateral double-diffused MOSFET （LDMOS）, the sectional channel is utilized to decrease the electric field in the n-drift region below the poly gate edge in the off-state, compared with the conventional single channel. Then the n-drift concentration can be increased to decrease the Kirk effect, while keeping off-state breakdown voltage Vbd unchanged. Meanwhile the influence of the n-drift concentration and the n-drift length Ldrift （the drain n＋ diffusion to gate spacing） which are related to the Kirk effect is discussed. The trade-offs between Rdson.Area, breakdown voltage Vbd and the electrical safe operating area （e-SOA） performance of LDMOS are considered also. Finally the proposed planar active-gap LDMOS devices with varied values of Ldria are experimentally demonstrated. The experimental results show that the Kirk effect can be greatly suppressed with slight increase in the Rdson.Area parameter.
文摘为了更精确预测基于0.18μm工艺的40 V NLDMOS器件实际应用条件下的热载流子寿命,介绍了一种通过可靠性测试和计算机辅助数学解析相结合的热载流子可靠性寿命预计方法。该方法基于实际直流状态下的热载流注入测试数据,结合TCAD仿真,对测试结果进行了线性函数、多次函数、幂函数、指数函数及Dreesen R函数拟合;通过分析当前业界LDMOS器件的热载流子注入测试主流模型预测精度的局限性,找出了最优热载流子模型,提出了适合Python语言编程的改进型Dreesen R模型;通过数学解析推导方法以及基于Python语言的计算机辅助编程计算,得出了栅极以及漏极全工作电压范围内的热载流子参数退化曲线;通过模拟工作波形不同上升沿及下降沿的函数曲线、上升及下降时间以及不同占空比,得出随着时间变化的交直流转换因子曲线。最终新的测试项目可以通过不同电压下的直流状态下测试结果以及已经得到的交直流转换因子曲线,来直接获取工作场景交流状态的热载流子寿命。该评估方法解决了采用直流状态下的测试来解决现场复杂应用波形的热载流子寿命评估难题,较大节省了测试时间,提高了寿命预测精度。
基金supported by the State Key Development Program for Basic Research of China (No. 2003CB314901)
文摘Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a thermionic-field-diffusion model that is used to the analyze the performance of an abrupt HBT with a heavydoped base, the conclusion is made that, although the BGN effect makes the currents obviously change due to the modification of the intrinsic carrier density, the band offsets disturbed by the BGN effect should also be taken into account in the analysis of the electrical characteristics of abrupt HBTs. In addition, the BGN effect changes the bias voltage for the onset of Kirk effects.
