Al基栅介质在SiC基MOS器件中界面与电学特性研究

As a representative of wide band gap semiconductor power devices and a new generation revolution of power electronics technique, Silicon Carbide (SiC) metal-oxide-semiconductor transistors (MOSFET) have great potential on energy conservation in smart power grids, rail transit, electric vehicles and clean energy fields. Nevertheless, the SiC based MOSFETs with SiO2 gate dielectric are suffering from low carrier mobility, high density of interfacial state, low critical electric field and high leakage current and being limited in applications. Based on the requirement, the goal of the proposal is to deposit Al2O3,AlN and AlON on SiC by chemical vapour deposition as gate dielectric films with properties of wide band gap, high critical electric field and dielectric constants. Then study the interfacial control of Al2O3 and SiC by using AlN and AlON dielectric films comprehensively, decrease the density of interfacial state and leakage current, and increase the carrier mobility of 4H-SiC based MOSFETs. Important results have been obtained during the initial research period. The execution of the proposal will play an important role and lays solid foundation on development and application of SiC based MOSFET power devices.

以碳化硅（SiC）金属-氧化物-半导体场效应晶体管(MOSFET)为代表的宽禁带半导体电力电子器件在节约能源方面具有巨大的应用潜力，可广泛应用于智能电网，轨道交通，电动汽车，清洁能源等领域，是新一代电力电子技术革命最具代表性的器件之一。然而目前以SiO2为栅介质的SiC基MOSFET器件的载流子迁移率低、界面态密度高、临界电场低及漏电流高等缺点限制了其在各领域的应用。基于此需求，本项目的研究目标是利用Al2O3、AlN和AlON薄膜禁带宽度大，临界场强高和介电常数高等特点，通过化学气相沉积等技术生长AlN和AlON栅介质薄膜，对Al2O3与4H-SiC的界面调控进行全面研究，降低其界面态密度和器件的漏电流，从而实现提高SiC基MOSFET器件载流子迁移率的目的。前期研究已取得重要结果，项目的实施将对SiC基MOSFET功率器件的发展起到重要作用并为将来应用打下坚实的基础。

以碳化硅（SiC）金属-氧化物-半导体场效应晶体管(MOSFET)为代表的宽禁带半导体电力电子器件在节约能源方面具有巨大的应用潜力，可广泛应用于智能电网，轨道交通，电动汽车，清洁能源等领域，是新一代电力电子技术革命最具代表性的器件之一。本项目利用Al2O3、AlN和AlON薄膜禁带宽度大，临界场强高和介电常数高等特点，通过原子层沉积等技术生长Al2O3、AlN和AlON栅介质薄膜，对Al2O3与4H-SiC的界面调控进行全面研究，降低其界面态密度和器件的漏电流，从而提高了4H-SiC基MOSFET器件电子迁移率，获得了工业化1200V/20A SiC MOSFET器件，并在充电桩上获得应用验证，项目的实施对SiC基MOSFET功率器件的发展起到重要作用并为将来的应用奠定坚实的基础。