ISSN:
1573-4854
Keywords:
wide gap amorphous silicon
;
photoluminescence
;
electroluminescence
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract A series of samples of hydrogenated amorphous silicon (a-Si:H) was prepared from silane diluted highly with He by the microwave electron-cyclotron-resonance PE CVD. Such a wide gap (E≥2.0 eV) a-Si:H emits room temperature photoluminescence (PL) in the visible region. We attempt to reveal the microscopic origin of this PL by monitoring variations of PL intensity vs frequency of infrared vibrations in the vicinity of 2100 cm−1. We find that oligosilanes -(SiH2)n- act as one type of possible luminescence centres. We report also on room temperature electroluminescence (EL) from p-i-n junctions. Surprisingly, and unlike p-i-n structures from standard a-Si:H, weak EL radiation with external quantum efficiency of the order of 10−5% is emitted under reverse bias only. EL and PL emission spectra resemble strongly each other, except high energy wing of the EL spectrum. This high energy widening indicates the participation of hot electrons in the EL excitation mechanism.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009692300389
Permalink
