Advanced Gate Dielectrics for Silicon Carbide Metal Oxide Semiconductor Application

用于碳化硅金属氧化物半导体应用的先进栅极电介质

• 批准号: 9906255
• 负责人: Veena Misra
• 金额: $ 17.99万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-10-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9906255&HistoricalAwards=false
• 关键词: Advanced; Gate; Dielectrics; Silicon; Carbide

9906255MisraSilicon carbide is an attractive material for high power, high frequency and high temperature applications. The ability of SiC to grow insulating SiO2 layers by thermal oxidation has been used in the fabrication of metal oxide semiconductor, MOS, devices such as field effect transistors, FETs. Significant research has been conducted on the SiC/SiO2 interface, but to date, i) a high density of interface states and fixed oxide charge and ii) poor reliability limit the functionality of SiC FET devices. Additionally, differences have been observed in the interface state densities between the 6H and 4H polytypes that are not understood, but may be related to differences between the band structures of these two polytypes, or alternatively to differences in the way suboxide, SiOx, bonding in the thermally grown oxide lines up with the interface band structure. The electric field in the SiO2 layer is higher than the peak field in the semiconductor by the ratio of dielectric constants. Since SiC devices are operated at very high electric fields, the gate dielectric field can become precariously high resulting in reliability problems.This proposal will investigate several areas that are currently challenging the successful development of high performance SiC MOS devices. First, an atomic level understanding of the interfacial properties of SiO2 and SiC and its effect on the channel mobility must be obtained through electrical and analytical techniques. The disparate behavior between the 6H and 4H SiC polytypes is not understood and needs to be explored at the atomic level. Additionally, the implementation of advanced dielectrics on SiC to improve reliability problems must also be considered. SiC devices are operated at higher fields than Si devices. Therefore, a dielectric with a higher dielectric constant than SiO2 will experience a lower electric field. This warrants the investigation of high-K dielectrics such as Si3N4,A12O3, Ta2O5, TiO2 and ZrSiO4, etc. Many of these dielectrics are already being aggressively studied for their potential implementation on Si.This program address the interfacial issues discussed above by applying remote plasma-assisted processing and rapid thermal processing to the formation of SiC-dielectric interfaces. This includes interfacial nitridation and implementation of alternative high-K dielectrics. The program will combine advanced analytical approaches to interface characterization, and as for Si device technology establish important links betweenelectrical behavior and atomic scale structure and bonding.***

9906255 Misra碳化硅是一种有吸引力的高功率、高频和高温应用材料。 SiC通过热氧化生长绝缘SiO2层的能力已经用于制造金属氧化物半导体MOS器件，例如场效应晶体管FET。 已经对SiC/SiO2界面进行了大量研究，但迄今为止，i）高密度的界面态和固定的氧化物电荷以及ii）差的可靠性限制了SiC FET器件的功能。 此外，已经观察到6 H和4 H多型体之间的界面态密度的差异，这是不理解的，但可能与这两种多型体的能带结构之间的差异有关，或者与热生长氧化物中的低价氧化物SiOx键合与界面能带结构对齐的方式的差异有关。SiO2层中的电场比半导体中的峰值电场高出介电常数之比。 由于SiC器件在非常高的电场下工作，栅极介电场可能变得不稳定，导致可靠性问题。本提案将研究目前挑战高性能SiC MOS器件成功开发的几个领域。 首先，必须通过电学和分析技术获得SiO2和SiC的界面性质及其对沟道迁移率的影响的原子级理解。 6 H和4 H SiC多型体之间的不同行为尚未被理解，需要在原子水平上进行探索。 此外，还必须考虑采用先进的SiC陶瓷来提高可靠性问题。 SiC器件在比Si器件更高的场下操作。 因此，介电常数比SiO2高的电介质将经历较低的电场。 这保证了调查的高K陶瓷，如Si 3 N4，A12 O3，Ta 2 O 5，TiO 2和ZrSiO 4等，这些陶瓷中的许多已经被积极研究其潜在的实施上Si.This程序解决了界面问题，通过应用远程等离子体辅助处理和快速热处理形成的SiC-电介质界面。 这包括界面氮化和实施替代高K值氮化。 该计划将结合联合收割机先进的分析方法，以界面表征，并为硅器件技术建立电气行为和原子尺度结构和键合之间的重要联系。