کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7224410 1470569 2018 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Study of GaN/AlGaN photocathode with variable aluminum AlxGa1−xN material in emission layer
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی (عمومی)
پیش نمایش صفحه اول مقاله
Study of GaN/AlGaN photocathode with variable aluminum AlxGa1−xN material in emission layer
چکیده انگلیسی
To introduce the built-in electric field in photoelectron emission layer, the GaN/AlGaN photocathode with variable aluminum (Al) AlxGa1-xN material in emission layer was grown. This sample was treated with surface cleaning and Cs/O activation to achieve negative electron affinity (NEA) status. The vacuum degree changes with heating temperature in the ultra-high vacuum (UHV) chamber indicated that almost all the carbon and oxygen residua were removed from GaN surface by chemical cleaning alone. The introduction of O after Cs deposition on GaN surface made a comparatively high photocurrent increase, which was observed for GaN photocathode for the first time and could be well explained with the Ga-O-Cs dipole model proposed before. High quantum efficiencies (QEs) were achieved in the wavelength from 240 nm to 275 nm for this sample, and the lower QEs at longer wavelengths can be explained with the small optical absorption coefficient of AlxGa1-xN material.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optik - Volume 158, April 2018, Pages 363-367
نویسندگان
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