同步辐射红外谱学和显微成像研究场效应下半导体－绝缘介质界面电荷动力学

各种新材料在场效应晶体管中的应用是当前新型器件的研究热点，也面临着许多复杂的新问题，其中半导体和栅绝缘介质的界面电荷动力学，以及材料在电场作用下的行为是人们关心的核心问题。电荷调制的红外谱学为研究半导体和栅绝缘介质的界面间的电子激发和输运、以及电场对介电系数的影响等关键问题提供了独特的、重要的谱学探针。但纳米尺度的半导体和栅绝缘介质的界面电荷积累层，以及位于远红外波段的低频红外声子模式给常规红外谱学测量带来困难。同步辐射红外辐射的高亮度以及远红外区强度优势，为开展此项研究提供了强有力的支持。我们通过发展同步辐射红外谱学和显微成像技术，建立复杂材料电场原位的谱学研究测试方法，研究场效应下半导体和栅绝缘介质界面的电子激发、载流子分布和输运，以及场效应对介电系数的影响，为深入理解输运机制、探寻新材料及其在器件中的应用提供物理依据，也为研究电场效应调控材料性质提供了极有效的方法。

The application of new novel materials to field effect transistor is the current research focus of new type electronic component. However, it is still facing many complex new problems. The charge dynamics of the interface between semiconductor and gate dielectric, as well as the behvior of matrials under electric field are the key points. Charge modulation infrared spectroscopy provides a unique and important spectroscopic probe for the studying these key problems such as the excitation and transport in the interface between the semiconductor and gate dielectric, the modification of electric field on the dielectric constant and so on. But it is difficult for the infrared spectroscopy measurement using conventional thermal source because the charge accumulation layer at the interface is in nanoscale, and the low frequency infrared phonon modes which have important influence on the dielectric constant are located at far infrared region. The high brightness and more flux in far infrared region of Synchrotron infrared soruce provides a powerful support for the study. In this application, we will develop synchrotorn infrared spectroscopy and imaging technique and estabish a spectrospic probe platform for the studing of the effect of electric field on complex materials. Based on the platform, we will study the electron excitation and charge-carrier distribution and transport in the interface between semiconductor and gate dielectric, the tunable dielectric constant under electric field. The study will be very interesting to deeply understanding the transport mechanism, exploring new materials and its application in the field effect transistor. It also provides a very effective method for the studying the manipulation and control of material property under electric field.