GaN MOS Capacitors and FETs on Plasma-Etched GaN Surfaces
GaN MOS Capacitors and FETs on Plasma-Etched GaN Surfaces
复制标题
等离子蚀刻 GaN 表面上的 GaN MOS 电容器和 FET
DOI：
10.1007/s11664-008-0617-y
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发表时间：
2009
影响因子：
2.1
通讯作者：
T. Chow
中科院分区：
文献类型：
--
作者：
K. Tang;W. Huang;T. Chow
测量了在生长表面、使用反应离子蚀刻（RIE）的干法蚀刻表面和干法蚀刻后的湿法蚀刻处理表面上制造的氮化镓（GaN）金属氧化物半导体（MOS）电容器和场效应晶体管（FET）的电特性。电容和电导技术被用来获得电容器的MOS特性。仅使用RIE等离子体干法蚀刻工艺的器件在低频累积区具有较差的良率和噪声电容。干/湿蚀刻处理的样品具有更负的紫外（UV）辅助电容-电压（CV）偏移，和更高的界面态密度，但具有相似的表面电位波动。测量了生长态GaN MOSFET的阈值电压为2 V，干/湿蚀刻MOSFET的阈值电压为1V。在生长态GaN晶片和干/湿蚀刻GaN晶片上的长沟道（Lchá= 100 μm）MOSFET的最大场效应迁移率分别为167 × cm 2 × V −1ás− 1和119 × cm 2 × V −1ás−1。较高的界面陷阱密度和较低的场效应迁移率表明，等离子体刻蚀后湿法刻蚀只能部分去除RIE损伤。
The electrical characteristics of gallium nitride (GaN) metal-oxide-semiconductor (MOS) capacitors and field-effect transistors (FETs) made on as-grown surfaces, dry-etched surfaces using reactive-ion etching (RIE), and wet-etch treated surfaces after the dry etch were measured. Capacitance and conductance techniques were used to obtain the MOS properties for capacitors. Devices with only an RIE plasma dry-etch process have poor yield and noisy capacitance in the low-frequency accumulation region. Those on dry/wet-etch treated samples have more negative ultraviolet (UV) assistant capacitance-voltage (CV) shift, and higher interface-state densities than those on as-grown samples, but have similar surface potential fluctuation. Threshold voltages of 2áV for an as-grown GaN MOSFET and 1áV for a dry/wet-etched MOSFET were measured. Maximum field-effect mobility for long-channel (Lchá=á100áμm) MOSFETs on the as-grown GaN wafer and the dry/wet-etched GaN wafer were obtained as 167ácm2áV−1ás−1and 119ácm2áV−1ás−1, respectively. The higher interface trap density and lower field-effect mobility indicate that post-plasma-etch wet etching can only partially remove the damages from RIE.