TY - JOUR
T1 - High-energy heavy-ion induced physical and surface-chemical modifications in polycrystalline cadmium sulfide thin films
AU - Chandramohan, S.
AU - Sathyamoorthy, R.
AU - Sudhagar, P.
AU - Kanjilal, D.
AU - Kabiraj, D.
AU - Asokan, K.
AU - Ganesan, V.
AU - Shripathi, T.
AU - Deshpande, U. P.
PY - 2009/3
Y1 - 2009/3
N2 - The effect of high electronic energy deposition on the structure, surface topography, optical properties, and electronic structure of cadmium sulfide (CdS) thin films have been investigated by irradiating the films with 100 MeV Ag+7 ions at different ion fluences in the range of 1012-1013 ions/cm2. The CdS films were deposited on glass substrate by thermal evaporation, and the films studied in the present work are polycrystalline with crystallites preferentially oriented along (002)-H direction. It is shown that swift heavy ion (SHI) irradiation leads to grain agglomeration and hence an increase in the grain size at low ion fluences. The observed lattice compaction was related to irradiation induced polygonization. The optical band gap energy decreased after irradiation, possibly due to the combined effect of change in the grain size and in the creation of intermediate energy levels. Enhanced nonradiative recombination via additional deep levels, introduced by SHI irradiation was noticed from photoluminescence (PL) analysis. A shift in the core levels associated with the change in Fermi level position was realized from XPS analysis. The chemistry of CdS film surface was studied which showed profound chemisorption of oxygen on the surface of CdS.
AB - The effect of high electronic energy deposition on the structure, surface topography, optical properties, and electronic structure of cadmium sulfide (CdS) thin films have been investigated by irradiating the films with 100 MeV Ag+7 ions at different ion fluences in the range of 1012-1013 ions/cm2. The CdS films were deposited on glass substrate by thermal evaporation, and the films studied in the present work are polycrystalline with crystallites preferentially oriented along (002)-H direction. It is shown that swift heavy ion (SHI) irradiation leads to grain agglomeration and hence an increase in the grain size at low ion fluences. The observed lattice compaction was related to irradiation induced polygonization. The optical band gap energy decreased after irradiation, possibly due to the combined effect of change in the grain size and in the creation of intermediate energy levels. Enhanced nonradiative recombination via additional deep levels, introduced by SHI irradiation was noticed from photoluminescence (PL) analysis. A shift in the core levels associated with the change in Fermi level position was realized from XPS analysis. The chemistry of CdS film surface was studied which showed profound chemisorption of oxygen on the surface of CdS.
UR - http://www.scopus.com/inward/record.url?scp=58349090212&partnerID=8YFLogxK
U2 - 10.1007/s00339-008-4866-7
DO - 10.1007/s00339-008-4866-7
M3 - Article
AN - SCOPUS:58349090212
SN - 0947-8396
VL - 94
SP - 703
EP - 714
JO - Applied Physics A: Materials Science and Processing
JF - Applied Physics A: Materials Science and Processing
IS - 3
ER -