The space-charge(SC)model and Teorell-Meyer-Sievers(TMS)model combined with irreversible thermodynamics model are applied to predict the transport coefficients of nanofiltration membranes in single electrolyte solutio...The space-charge(SC)model and Teorell-Meyer-Sievers(TMS)model combined with irreversible thermodynamics model are applied to predict the transport coefficients of nanofiltration membranes in single electrolyte solution.The reflection coefficient has been numerically calculated by the SC model and analytically calculated by TMS model.The results show that the reflection coefficient approaches unit in the range of low-concentration regime and approaches zero in the range of high-concentration.While the diffusion coefficients ratio of co-ion over counterion is less than 1.0,the reflection coefficient is positive over the whole concentration range.When the ratio is larger than 1.0,the reflection coefficient is negative in a certain intermediate concentration region.And the increase of the surface charge density and the decrease of the pore radius cause the increase in the reflection coefficient.The SC model and TMS model show good agreement in the calculation of the reflection coefficient when the dimensionless potential gradient in the pore surfaces is less than 1.0 and the pore radius is less than 5.0 nm.展开更多
为了优化传统AlGaN/GaN high electron mobility transistors结构表面电场分布,提高器件击穿电压和可靠性,本文利用不影响AlGaN/GaN异质结极化效应的Si3N4钝化层电荷分布,提出了一种Si3N4钝化层部分固定正电荷AlGaN/GaN high electron m...为了优化传统AlGaN/GaN high electron mobility transistors结构表面电场分布,提高器件击穿电压和可靠性,本文利用不影响AlGaN/GaN异质结极化效应的Si3N4钝化层电荷分布,提出了一种Si3N4钝化层部分固定正电荷AlGaN/GaN high electron mobility transistors新结构.Si3N4钝化层中部分固定正电荷通过电场调制效应使表面电场分布中产生新的电场峰而趋于均匀.新电场峰使得新结构栅边缘和漏端高电场有效降低,器件击穿电压从传统结构的296V提高到新结构的650V,而且可靠性改善.通过Si3N4与AlGaN界面横、纵向电场分布,说明了产生表面电场峰的电场调制效应,为设计Si3N4层部分固定正电荷新结构提供了科学依据.Si3N4钝化层部分固定正电荷的补偿作用,使沟道二维电子气浓度增加,导通电阻减小,输出电流提高.展开更多
文摘The space-charge(SC)model and Teorell-Meyer-Sievers(TMS)model combined with irreversible thermodynamics model are applied to predict the transport coefficients of nanofiltration membranes in single electrolyte solution.The reflection coefficient has been numerically calculated by the SC model and analytically calculated by TMS model.The results show that the reflection coefficient approaches unit in the range of low-concentration regime and approaches zero in the range of high-concentration.While the diffusion coefficients ratio of co-ion over counterion is less than 1.0,the reflection coefficient is positive over the whole concentration range.When the ratio is larger than 1.0,the reflection coefficient is negative in a certain intermediate concentration region.And the increase of the surface charge density and the decrease of the pore radius cause the increase in the reflection coefficient.The SC model and TMS model show good agreement in the calculation of the reflection coefficient when the dimensionless potential gradient in the pore surfaces is less than 1.0 and the pore radius is less than 5.0 nm.
文摘为了优化传统AlGaN/GaN high electron mobility transistors结构表面电场分布,提高器件击穿电压和可靠性,本文利用不影响AlGaN/GaN异质结极化效应的Si3N4钝化层电荷分布,提出了一种Si3N4钝化层部分固定正电荷AlGaN/GaN high electron mobility transistors新结构.Si3N4钝化层中部分固定正电荷通过电场调制效应使表面电场分布中产生新的电场峰而趋于均匀.新电场峰使得新结构栅边缘和漏端高电场有效降低,器件击穿电压从传统结构的296V提高到新结构的650V,而且可靠性改善.通过Si3N4与AlGaN界面横、纵向电场分布,说明了产生表面电场峰的电场调制效应,为设计Si3N4层部分固定正电荷新结构提供了科学依据.Si3N4钝化层部分固定正电荷的补偿作用,使沟道二维电子气浓度增加,导通电阻减小,输出电流提高.
