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没有缓冲区的化高电子流动性在上的异构结构
Saptarsi Ghosh1,2, Martin Frentrup1, Alexander M Hinz1
1Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK.
Advanced materials (Deerfield Beach, Fla.)
|January 23, 2025
概括
研究人员开发了一种在上生长化 (GaN) 的缓冲式方法,显著降低了高电子流动性晶体管 (HEMT) 的热电阻. 这一创新通过改善散热来提高设备的效率和寿命.
科学领域:
- 材料科学 材料科学 材料科学
- 半导体物理 半导体物理
- 纳米技术纳米技术
背景情况:
- 在不匹配的上,厚厚的变形缓冲器对于III-V半导体表是必不可少的,但GaN-on-Si HEMT中的III-化缓冲器会产生高热阻.
- 这种热阻阻碍了热的提取,对设备的效率和运行寿命产生了负面影响.
研究的目的:
- 通过绕过传统的缓冲层,在基板上直接生长化 (GaN) 的新方法.
- 调查实现高质量的GaN脱皮层没有缓冲器的可行性,重点关注压力管理和缺陷减少.
- 评估由此产生的没有缓冲区的GaN-on-Si结构的热和电子特性.
主要方法:
- 利用金属有机蒸汽相表 (MOVPE) 在六英寸的基板上的化 (AlN) 核化层上直接增长GaN.
- 采用生长压力调节技术,以防止在缺少缓冲层的情况下发生皮层裂.
- 通过测量线程位移密度和通过霍尔效应测量和舒布尼科夫-德-哈斯振荡分析二维电子气体 (2DEG) 属性来表征材料质量.
主要成果:
- 在没有变态缓冲器的上成功实现了GaN的直接增长,实现了与缓冲结构相比较的线程位移密度.
- 显示了显著降低的GaN-to-substrate热电阻 (11 ± 4) m2 K GW-1,比传统的GaN-on-Si低一个数量级.
- 获得了高质量的AlGaN/AlN/GaN异质连接,其2DEG显示室温霍尔运动性超过2000cm2V-1s-1和清晰的舒布尼科夫-德-哈斯振荡.
结论:
- 没有缓冲器的GaN-on-Si方法可以大幅降低热阻,为更节能的功率晶体管铺平了道路.
- 这种方法为III-化物研究提供了一个新的平台,使得在宽带间隙准2D系统中对电子动态的基本研究成为可能.
- 获得的材料质量和电子性能与最好的非原生基板相美,突出了这项技术的潜力.
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