Liquid-phase epitaxy of In-doped PbTe for the application of mid-infrared semiconductor laser

• Published in: The Journal of physics and chemistry of solids Vol. 69; no. 2; pp. 727 - 729
• Main Authors: Yasuda, Arata, Suto, Ken, Takahashi, Yatsuhiro, Kato, Yoshikazu, Oyama, Yutaka, Nishzawa, Jun-ich
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01-02-2008; Elsevier
• Subjects: A. Semiconductors; A. Thin films; B. Epitaxial growth; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Optical properties; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Ii-vi semiconductors; Lasers; Optics; Physics; Semiconductor lasers; laser diodes; A. Thin films; B. Epitaxial growth; D. Optical properties; A. Semiconductors; LPE; TDS; Epitaxial layers; Semiconductor materials; Vapor pressure; Doping; Threshold current; Mass spectroscopy; Hall effect; Mid infrared radiation; Thin films; Lead tellurides; Semiconductor lasers; p n junctions; Electron mobility; Carrier density; Homojunctions
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2007.07.066

Indium-doped PbTe epitaxial layers and pn homojunction diodes were grown on PbTe substrate using the temperature-difference method under controlled vapor pressure (TDM-CVP) liquid-phase epitaxy (LPE). The activation ratio of indium donor in the PbTe epitaxial layer was as high as 80%, and we achieved high electron concentrations up to
n
D=5×10
19
cm
−3. In view of the enhanced electron mobility, it is shown that the optimum Te vapor pressure for an In-doped PbTe epitaxial layer is about 2×10
−5
Torr at 470
°C, which agrees well with the results for undoped and heavily Bi-doped PbTe epitaxial layers. In-doped
n
+-PbTe layer was successfully applied for the fabrication of broad contact pn junction lasers and excellent lasing emissions were achieved, characteristics as compared to Bi-doped and -undoped cladding layers. The threshold current for a broad area diode is 200
A/cm
2 at 15
K and 2.7
kA/cm
2 at 77
K.