基于HfO2栅介质的Ga2O3 MOSFET器件研制  

Research and Fabrication of Ga2O3 MOSFET Device with HfO2 Gate Dielectric

作　　者：韩婷婷[1] 吕元杰[1] 刘沛[2] 敦少博[1] 顾国栋[1] 冯志红[1] 

机构地区：[1]专用集成电路重点实验室,石家庄050051 [2]中国航天标准化与产品保证研究院,北京100071

出　　处：《半导体技术》2018年第3期177-180,232,共5页Semiconductor Technology

摘　　要：采用金属有机化学气相沉积（MOCVD）方法在（010）Fe掺杂半绝缘Ga2O3同质衬底上外延得到n型β-Ga2O3薄膜材料,材料结构包括400 nm的非故意掺杂Ga2O3缓冲层和40 nm的Si掺杂Ga2O3沟道层。基于掺杂浓度为2.0×1018cm-3的n型β-Ga2O3薄膜材料,采用原子层沉积的25 nm的HfO2作为栅下绝缘介质层,研制出Ga2O3金属氧化物半导体场效应晶体管（MOSFET）。器件展示出良好的电学特性,在栅偏压为8 V时,漏源饱和电流密度达到42 m A/mm,器件的峰值跨导约为3.8 m S/mm,漏源电流开关比达到108。此外,器件的三端关态击穿电压为113 V。采用场板结构并结合n型Ga2O3沟道层结构优化设计能进一步提升器件饱和电流和击穿电压等电学特性。n-type β-Ga2O3 thin-film material was epitaxially grown by metal organic chemical vapor deposition （MOCVD） on the （010） Fe-doped semi-insulating Ga2O3 substrate. The material structure consisted of a 400 nm unintentional doping Ga2O3 buffer layer and a 40 nm Si-doped channel layer. The Ga2O3 metal-oxide-semiconductor field-effect transistor （MOSFET） was fabricated based on the n-type β-Ga2O3 film with a doping concentration of 2. 0 × 1018 cm-3. 25 nm HfO2 was deposited by atomic layer deposition as the gate dielectric. The device exhibits good electrical properties. The drain source saturation current density of the fabricated device reaches 42 m A/mm at Vgsof 8 V,and the peak transconductance is about 3. 8 m S/mm,and the on-to-off current ratio reaches 108. Moreover,the three-terminal offstate breakdown voltage of the fabricated device is 113 V. The electrical performances of the Ga2O3 MOSFET,such as the saturation current and breakdown voltage can be further improved by the optimized n-type Ga2O3 channel structure and introducing field plate structure.

关 键 词：β-Ga2O3 金属氧化物半导体场效应晶体管(MOSFET) HfO2介质层 FE掺杂 漏源饱和电流 击穿电压 

分 类 号：TN386[电子电信—物理电子学] TN304.2