Pulsed laser deposition of indium on the CdTe crystal surface for contact formation

Kateryna Zelenska; Volodymyr Gnatyuk; Vitaliy Veleschuk; Toru Aoki

doi:10.1117/12.2323380

13 September 2018 Pulsed laser deposition of indium on the CdTe crystal surface for contact formation

Kateryna Zelenska, Volodymyr Gnatyuk, Vitaliy Veleschuk, Toru Aoki

Proceedings Volume 10762, Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XX; 1076218 (2018) https://doi.org/10.1117/12.2323380
Event: SPIE Optical Engineering + Applications, 2018, San Diego, California, United States

Abstract

Laser processing of high-resistivity p-CdTe semiconductor crystals and CdTe-metal interfaces has been used to obtain diode structures for X/γ-ray detectors. The relative simple techniques of laser doping and metallization of the CdTe surface have been studied. Deposition of In onto the CdTe crystals was performed using YAG:Nd laser pulses (1064 nm, 8 ns) in two ways: (a) laser transfer of a thin In film, pre-deposited on the glass substrate by laser ablation of an In target irradiated through the glass; (b) laser incorporation of In into the CdTe surface region by irradiation of an In target through the CdTe. Deposited In islands were revealed on the CdTe surface by SEM imaging. Photoconductivity spectra and I-V characteristics of the crystals before and after laser processing were measured. An increase in photosensitivity, particularly in the short wavelength region was observed for the metallized samples that was attributed to a decrease of the surface recombination velocity because of the built-in electric field due to the surface barrier formation. The structures demonstrated rectifying I-V characteristics. The resistivity of the metallized CdTe surface region exceeded that of the initial crystals in a few times therefore, the model of micro-p-n junctions, formed by simultaneous laser deposition of In and doping of local CdTe regions as result of penetration of In atoms (donors) into a thin CdTe surface layer, was considered. Micro-diodes, formed by laser-induced creation of n-type micro-regions, connected in the opposite direction, can be a reason of increased resistivity of the metalized CdTe surface.

Citation Download Citation

Kateryna Zelenska, Volodymyr Gnatyuk, Vitaliy Veleschuk, and Toru Aoki "Pulsed laser deposition of indium on the CdTe crystal surface for contact formation", Proc. SPIE 10762, Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XX, 1076218 (13 September 2018); https://doi.org/10.1117/12.2323380

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available