Bulk single crystals and physical properties of β-(AlxGa1-x)2O3 (x=0-0.35) grown by the Czochralski method

被引：20

作者：

Galazka, Zbigniew ^{[1
]}

Fiedler, Andreas ^{[1
]}

Popp, Andreas ^{[1
]}

Ganschow, Steffen ^{[1
]}

Kwasniewski, Albert ^{[1
]}

Seyidov, Palvan ^{[1
]}

Pietsch, Mike ^{[1
]}

Dittmar, Andrea ^{[1
]}

Anooz, Saud Bin ^{[1
]}

Irmscher, Klaus ^{[1
]}

Suendermann, Manuela ^{[1
]}

Klimm, Detlef ^{[1
]}

Chou, Ta-Shun ^{[1
]}

Rehm, Jana ^{[1
]}

Schroeder, Thomas ^{[1
,2
]}

Bickermann, Matthias ^{[1
,3
]}

机构：

[1] Leibniz Inst Kristallzuchtung, Max Born Str 2, D-12489 Berlin, Germany

[2] Humboldt Univ, Inst Phys, Newtonstr 15, D-12489 Berlin, Germany

[3] Tech Univ Berlin, Inst Chem, Str 17 Juni 115, D-10623 Berlin, Germany

来源：

JOURNAL OF APPLIED PHYSICS | 2023年 / 133卷 / 03期

关键词：

BETA-GA2O3; PROGRESS;

D O I：

10.1063/5.0131285

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have systematically studied the growth, by the Czochralski method, and basic physical properties of a 2 cm and 2 in. diameter bulk beta-(AlxGa1-x)(2)O-3 single crystal with [Al] = 0-35 mol. % in the melt in 5 mol. % steps. The segregation coefficient of Al in the Ga2O3 melt of 1.1-1.2 results in a higher Al content in the crystals than in the melt. The crystals were also co-doped with Si or Mg. [Al] = 30 mol. % in the melt (33-36 mol. % in the crystals) seems to be a limit for obtaining bulk single crystals of high structural quality suitable for homoepitaxy. The crystals were either semiconducting (no intentional co-dopants with [Al] = 0-30 mol. % and Si-doped with [Al] = 15-20 mol. %), degenerately semiconducting (Si-doped with [Al] <= 15 mol. %), or semi-insulating ([Al] >= 25 mol. % and/or Mg-doped). The full width at half maximum of the rocking curve was 30-50 arcsec. The crystals showed a linear but anisotropic decrease in all lattice constants and a linear increase in the optical bandgap (5.6 eV for [Al] = 30 mol. %). The room temperature electron mobility at similar free electron concentrations gradually decreases with [Al], presumably due to enhanced scattering at phonons as the result of a larger lattice distortion. In Si co-doped crystals, the scattering is enhanced by ionized impurities. Measured electron mobilities and bandgaps enabled to estimate the Baliga figure of merit for electronic devices.

引用

页数：11

共 57 条

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