Characterization and Modeling of Cryogenic Ultralow-Noise InP HEMTs
Characterization and Modeling of Cryogenic Ultralow-Noise InP HEMTs
复制标题
低温超低噪声 InP HEMT 的表征和建模
DOI：
10.1109/ted.2012.2227485
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发表时间：
2013
影响因子：
3.1
通讯作者：
J. Grahn
中科院分区：
文献类型：
--
作者：
J. Schleeh;H. Rodilla;N. Wadefalk;P. Nilsson;J. Grahn
介绍了在10k下工作的超低噪声InP/InAlAs/InGaAs高电子迁移率晶体管（InP HEMTs）的详细s参数和噪声表征和建模。在10 K的最佳低噪声偏置下，与300 K相比，InP HEMT的截止频率fT提高了60%，直流跨导gm提高了100%。在10和300 K的不同偏置条件下，对小信号噪声模型进行了评估。在10 K时，建立了低噪声工作时最小噪声温度的偏置依赖性模型。阈值电压VT、gm、栅极源和栅极漏电容Cgs和Cgd的温度依赖性表明，优化后的InP HEMTs具有优异的低温噪声性能，是因为在10 K时，与300 K相比，最靠近栅极的载流子浓度受到了更大程度的限制。因此，在低温操作下，HEMT通道相对漏极电流Id的快速耗尽发生。
Detailed S-parameter and noise characterization and modeling of ultralow-noise InP/InAlAs/InGaAs high-electron mobility transistors (InP HEMTs) optimized for operation at 10 K are presented. At the optimum low-noise bias at 10 K, the InP HEMT exhibited a 60% improvement in cutoff frequency fT and a 100% improvement in dc transconductance gm compared with 300 K. A small-signal noise model was evaluated at different bias conditions at 10 and 300 K. The bias dependence of the minimum noise temperature at low-noise operation was modeled at 10 K. The temperature dependence of the threshold voltage VT, gm, and gate-source and gate-drain capacitances Cgs and Cgd indicated that the excellent cryogenic noise performance of optimized InP HEMTs is due to a higher degree of confinement in the carrier concentration closest to the gate at 10 K compared with 300 K. As a result, a fast depletion of the HEMT channel with respect to drain current Id occurs under cryogenic operation.