提出了一种改进的高电子迁移率晶体管寄生电阻提取方法，该方法利用了特殊偏置点（V_gs > V_th，V_ds = 0 V）的等效电路模型，推导了寄生电阻的表达式，采用半分析法对寄生电阻进行了优化。1 ~110 GHz S参数实测结果和仿真的S参数一致，证明该方法是有效的。

A physics-based analytical expression that predicts the charge, electrical field and potential distributions along the gated region of the GaN HEMT channel has been developed. Unlike the gradual channel approximation (GCA), the proposed model considers the non-uniform variation of the concentration under the gated region as a function of terminal applied voltages. In addition, the model can capture the influence of mobility and channel temperature on the charge distribution trend. The comparison with the hydrodynamic (HD) numerical simulation showed a high agreement of the proposed model with numerical data for different bias conditions considering the self-heating and quantization of the electron concentration. The analytical nature of the model allows us to reduce the computational and time cost of the simulation. Also, it can be used as a core expression to develop a complete physics-based transistor Ⅳ model without GCA limitation.

本文采用金属有机化学气相沉积（MOCVD）生长原位SiNx栅介质制备了用于Ka波段高功率毫米波应用的AlN/GaN金属绝缘体半导体高电子迁移率晶体管（MIS-HEMTs）。原位生长SiN_x栅介质显著抑制了栅反向漏电、栅介质/AlN界面态密度和电流坍塌。所研制的MIS HEMTs在V_GS= 2 V时最大饱和输出电流为2.2 A/mm，峰值跨导为509 mS/mm，在V_GS = -30 V时肖特基栅漏电流为4.7×10^-6 A/mm。采用0.15 μmT形栅技术，获得98 GHz的f_T和165 GHz的f_MAX。大信号测量表明，在连续波模式下，漏极电压V_DS = 8 V时，MIS HEMT在40 GHz下输出功率密度2.3 W/mm，45.2%的功率附加效率（PAE），而当V_DS增加到15 V时，功率密度提升到5.2 W/mm，PAE为42.2%。

本文采用等离子体增强原子层沉积（PEALD）生长的SiN_x栅介质制备了宽带应用的AlGaN/GaN金属绝缘体半导体高电子迁移率晶体管（MIS-HEMTs），并在直流、小信号及大信号测试中评估了该介质层对器件性能的提升。测试结果表明改进器件具有高质量界面、宽栅极控制范围、良好的电流崩塌控制等优势，并确认了其在超过5 GHz下工作时仍能保持较高的功率附加效率（PAE）。在5 GHz连续波模式下，漏极电压V_DS = 10 V时，MIS HEMT输出功率密度为1.4 W/mm，PAE可达到74.7%；V_DS增加到30 V时，功率密度提升到5.9 W/mm，PAE可保持在63.2%的水平；测试频率增加30 GHz，在相同的输出功率水平下，器件的PAE达到50.4%。同时，高质量栅极介电层还可允许器件承受高的栅极电压摆动：在功率增益压缩6 dB时，栅极电流保持在10^-4 A/mm。上述结果证实了该SiN_x栅介质对器件性能的提升，使其满足宽带应用的高效率、高功率和可靠性要求，为系统和电路的宽带设计提供器件级的保障。

有机电致发光（OLED）是目前最有竞争力的显示技术，市场占有量逐年攀升。高效、稳定的OLED，特别是深蓝光器件，性能仍需提升，其关键问题是高性能的电子传输材料的研发。这是由于有机分子难以获得较高电子迁移率，器件中的复合区域通常靠近电子传输层一侧，这就要求电子传输材料需要具有较高三线态能级来限域激子，尤其是高能量的蓝光激子。而高三线态（弱共轭）和高迁移率（强共轭）一直是有机分子设计中难以调和的矛盾，此外更宽的带隙也会导致较差的热稳定性，这些难题始终限制着OLED电子传输材料的发展。本文分类介绍了高性能的电子传输材料所需要具备的几点特性，包括热稳定性、光化学稳定性、电子迁移率、前线轨道能级和三重态能级等，并且综述了21世纪以来OLED小分子电子传输材料的重要研究进展，以期对未来开发理想的电子传输材料提供参考。

基于90 nm InP HEMT工艺，设计了一款220 GHz功率放大器太赫兹单片集成电路，该放大器采用片上威尔金森功分器结构实现了两路五级共源放大器的功率合成。在片测试结果表明，200~230 GHz频率范围内，功率放大器小信号增益平均值18 dB。频率为210~230 GHz范围内该MMIC放大器饱和输出功率优于15.8 mW，在223 GHz时最高输出功率达到20.9 mW，放大器芯片尺寸为2.18 mm×2.40 mm。

Holographic display has attracted widespread interest because of its ability to show the complete information of the object and bring people an unprecedented sense of presence. The absence of ideal recording materials has hampered the realization of their commercial applications. Here we report that the response time of a bismuth and magnesium co-doped lithium niobate (LN:Bi,Mg) crystal is shortened to 7.2 ms and a sensitivity as high as 646 cm/J. The crystal was used to demonstrate a real-time holographic display with a refresh rate of 60 Hz, as that of the popular high-definition television. Moreover, the first-principles calculations indicate that the electron mobility while Bi occupying Nb-site is significantly greater than that in Li-site, which directly induces the fast response of LN:Bi,Mg crystals when the concentration of Mg is above its doping threshold.Holographic display has attracted widespread interest because of its ability to show the complete information of the object and bring people an unprecedented sense of presence. The absence of ideal recording materials has hampered the realization of their commercial applications. Here we report that the response time of a bismuth and magnesium co-doped lithium niobate (LN:Bi,Mg) crystal is shortened to 7.2 ms and a sensitivity as high as 646 cm/J. The crystal was used to demonstrate a real-time holographic display with a refresh rate of 60 Hz, as that of the popular high-definition television. Moreover, the first-principles calculations indicate that the electron mobility while Bi occupying Nb-site is significantly greater than that in Li-site, which directly induces the fast response of LN:Bi,Mg crystals when the concentration of Mg is above its doping threshold.

采用气体源分子束外延（GSMBE）技术，研究了InP衬底上In_yAl_1-yAs线性渐变缓冲层对In_0.66Ga_0.34As/In_yAl_1-yAs高迁移率晶体管（HEMT）材料特性影响。研究了不同厚度和不同铟含量的In_yAl_1-yAs线性渐变缓冲层对材料的表面质量、电子迁移率和二维电子气浓度的影响。结果表明，在300 K（77 K）时，电子迁移率和电子浓度分别为8 570 cm²/（Vs）^-1（23 200 cm²/（Vs）-1）3.255E12 cm^-2（2.732E12 cm^-2）。当In_yAl_1-yAs线性渐变缓冲层厚度为50 nm时，材料的表面形貌得到了很好的改善，均方根粗糙度（RMS）为0.154 nm。本研究可以为HEMT器件性能的提高提供强有力的支持。

提出了一种用于InP 高电子迁移率晶体管（high electron mobility transistor，HEMT）的分布式小信号等效电路建模方法。在采用的模型中考虑了分布电容效应，通过加入三个分布电容来表征。为了精确建模，在提取寄生电容时考虑到寄生电感引入的误差，首先提取了寄生电感。在达到50 GHz的InP HEMT中，小信号建模方法的有效性得到了验证。此外，在2～50 GHz频率范围内，S参数建模误差小于4%，这也证明了所提出建模方法的高建模精度。