In:
Journal of Physics D: Applied Physics, IOP Publishing, Vol. 49, No. 11 ( 2016-03-23), p. 115101-
Abstract:
Restricted area heterojunctions, an array of lead sulfide colloidal quantum dots (PbS-CQDs) and crystalline silicon, are studied with a non-destructive remote contact light beam induced current (RC-LBIC) technique. As well as getting good quality active area images we observed an anomalous unipolar signal response for the PbS-CQD/ n -Si devices and a conventionally expected bipolar signal profile for the PbS-CQD/ p -Si devices. Interestingly, our simulation results consistently yielded a unipolar and bipolar nature in the signals related to the PbS-CQD/ n -Si and PbS-CQD/ p -Si heterostructures, respectively. In order to explain the physical mechanism involved in the unipolar signal response of the PbS-CQD/ n -Si devices, we propose a model based on the band alignment in the heterojunctions, in addition to the distribution of photo-induced excess majority carriers across the junction. Given that the RC-LBIC technique is well suited to this context, the presence of these two distinct mechanisms (the bipolar and unipolar nature of the signals) needs to be considered in order to have a better interpretation of the data in the characterization of an array of homo/heterojunctions.
Type of Medium:
Online Resource
ISSN:
0022-3727
,
1361-6463
DOI:
10.1088/0022-3727/49/11/115101
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2016
detail.hit.zdb_id:
209221-9
detail.hit.zdb_id:
1472948-9
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