Long Lifetime Hole Traps at Grain Boundaries in CdTe Thin-Film Photovoltaics.
Long Lifetime Hole Traps at Grain Boundaries in CdTe Thin-Film Photovoltaics.
复制标题
DOI：
10.1103/physrevlett.115.218701
复制
发表时间：
2015-11
影响因子：
8.6
通讯作者：
B. Mendis;D. Gachet;J. Major;Ken Durose
中科院分区：
文献类型：
--
作者：
B. Mendis;D. Gachet;J. Major;Ken Durose
一种新的时间分辨阴极发光方法，通过光电效应产生脉冲电子束，用于探测单个CdTe晶界。激子在晶界内的寿命很短(≤为100ps)，并在晶界上迅速熄灭。然而，~47 meV的浅受主，被认为是由于氧，即使在它们浓度较高的晶界上，也可以起到长寿命空穴陷阱的作用。这为最近观察到的高掺杂CdTe在低温下的晶界跳跃电导提供了直接证据。
A novel time-resolved cathodoluminescence method, where a pulsed electron beam is generated via the photoelectric effect, is used to probe individual CdTe grain boundaries. Excitons have a short lifetime (≤100 ps) within the grains and are rapidly quenched at the grain boundary. However, a ~47 meV shallow acceptor, believed to be due to oxygen, can act as a long lifetime hole trap, even at the grain boundaries where their concentration is higher. This provides direct evidence supporting recent observations of hopping conduction across grain boundaries in highly doped CdTe at low temperature.