The influence of composition and unintentional doping on the two-dimensional electron gas density in AlGaN/GaN heterostructures

被引：4

作者：

Davidsson, SK ^{[1
]}

Gurusinghe, M ^{[1
]}

Andersson, TG ^{[1
]}

Zirath, H ^{[1
]}

机构：

[1] Chalmers, Dept Microtechnol & Nanosci, Microwave Electron Lab, S-41296 Gothenburg, Sweden

来源：

JOURNAL OF ELECTRONIC MATERIALS | 2004年 / 33卷 / 05期

关键词：

AlGaN/GaN; 2DEG density; heterostructures;

D O I：

10.1007/s11664-004-0199-2

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

We have studied the influence of Al content, AlGaN layer thickness, and unintentional background doping by oxygen on the two-dimensional electron gas (2DEG) density in AlGaN/GaN heterostructures. Hall measurements were made on samples grown with molecular beam epitaxy The 2DEG densities in the range 2-3 X 10(13) cm(-2) were measured. A one-dimensional Schrodinger-Poisson model was used to describe the heterostructure. The calculations gave two-dimensional electron densities in accordance with measured values. The electron density is very sensitive to the Al concentration in the AlGaN layer, whereas the sensitivity to layer thickness is small. Our Simulations also showed that the two-dimensional concentration increased 50% when the free-carrier concentration changed from 10(15) cm(-3) to 10(18) cm(-3). The relation between donor concentration and free-carrier concentration was found to agree when using oxygen ionization energy as a parameter.

引用

页码：440 / 444

页数：5

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