کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5425150 1395848 2007 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Scanning tunneling microscopy luminescence from nanoscale surface of GaAs(1 1 0)
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Scanning tunneling microscopy luminescence from nanoscale surface of GaAs(1 1 0)
چکیده انگلیسی

Scanning tunneling microscopy luminescence (STML) was induced from the nanometer scale surfaces of cleaved n-type and p-type GaAs(1 1 0) wafers by using of an ITO-coated optical fiber probe in an ultrahigh-vacuum chamber. The STML from n-type GaAs(1 1 0) surface was induced under negative sample bias when the applied bias exceeds a threshold voltage around −1.5 V. Whereas the STML from p-type GaAs(1 1 0) surface was induced under positive sample bias when the applied bias exceeds a threshold voltage around +1.5 V. The excitation energies at the threshold voltages are consistent with the band gap of GaAs (1.42 eV) at 295 K. The typical quantum efficiencies for n-type and p-type GaAs are about 3 × 10−5 and 2 × 10−4 photons/electron, respectively. The observed STML from are attributed to a radiative recombination of electron-hole pairs generated by a hole injection for n-type GaAs under negative sample bias and an electron injection for p-type GaAs under positive sample bias, respectively.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface Science - Volume 601, Issue 22, 15 November 2007, Pages 5280-5283
نویسندگان
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