晶格匹配InAlN/GaN HEMT沟道温度评估方法研究

Study on Channel Temperature Measurement of Lattice-Matched InAlN/GaN HEMT

首先分别利用直流电学法、脉冲电学法和微区拉曼光谱法测量了晶格匹配InAlN/GaN高电子迁移率晶体管(HEMT)的沟道温度,然后评估了各类评估方法的准确性。结果表明:直流电学法获得的温度值远低于拉曼光谱法,严重低估了HEMT工作时的沟道温度;脉冲电学法获得的温度值有所提升,但受限于水平空间分辨率,平均了源极-漏极之间的温度;微区拉曼光谱法能够准确获得沟道最高温度,但测量过程复杂,不适合评估封装器件。最后,提出了一种基于微光显微镜(EMMI)技术的微光电学法,获得了沟道温度的三角分布关系,得到了与拉曼光谱法一致的实验结果。该评估方法适合于实际生产。

Various experimental methods were used for measuring the channel temperature of lattice-matched InAlN/GaN high electron mobility transistors(HEMT), including the DC electrical method, pulse electrical method and micro-Raman spectroscopy measurement, then the accuracy of each method was evaluated. The results showed that the temperature obtained by DC electrical method was lower than that by Raman measurement, which seriously underestimated the channel temperature. The temperature obtained by pulse electrical method had been improved, but the temperature between source and drain was averaged due to the limitation of horizontal spatial resolution. The maximum channel temperature could be accurately obtained by micro-Raman spectroscopy. However, the measurement process was too complex to be applicable to the actual packaging device. Finally, a micro-light electrical method based on Emission Microscope(EMMI) technology was proposed. The triangular distribution of channel temperature was obtained, and the experimental results were consistent with the Raman spectroscopy method. This evaluation method was suitable for practical production.