Investigation of p-type SnO 2 :Zn ﬁlms deposited using a simpliﬁed spray pyrolysis technique K. Ravichandran ⇑ , K. Thirumurugan, N. Jabena Begum, S. Snega P.G. & Research Department of Physics, AVVM Sri Pushpam College (Autonomous), Poondi, Thanjavur 613 503, Tamil Nadu, India article info Article history: Received 3 May 2013 Accepted 8 May 2013 Available online 16 May 2013 Keywords: p-type SnO 2 :Zn ﬁlms Spray pyrolysis Transparent electronics Structural properties abstract Zinc doped SnO 2 ﬁlms were prepared using a simpliﬁed spray tech- nique and the inﬂuence of dopant concentration on structural, electrical, optical and surface morphological properties were ana- lysed in detail. XRD results showed that all the ﬁlms were poly- crystalline SnO 2 with tetragonal rutile structure. The transition of preferential orientation from (2 1 1) to (1 0 1) plane was found to take place beyond 20 at.% of Zn doping level. Hall measurements showed that the ﬁlms exhibited p-type conductivity when the dop- ing concentration was increased beyond 20 at.%. The average trans- mittance of the SnO 2 :Zn ﬁlms were in the range of 80–90% in the visible region. The enhancement in the PL emission can be corre- lated with the decrease in the grain size observed from the SEM images and the sharpening of defect related peaks supplemented the formation of trapped states (introduction of dangling bonds) at higher Zn concentrations. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction Nowadays, a lot of attention has been paid to transparent conducting tin oxide ﬁlms due to its un- ique desirable properties such as low electrical resistivity, high transmittance in the visible range, wide band gap (E g  3.6 eV) [1], high infrared reﬂectance, nontoxicity and abundancy in nature. It has a wide range of applications such as window layers [2–4], heat reﬂectors in solar cells [5], varistors and optoelectronic devices [6], gas sensors [7] and photo-catalysts [8]. Recently p-type SnO 2 thin ﬁlms fabricated with a lower valence cation as an acceptor dopant have attracted the interest of the researchers [9–15]. A new ﬁeld called ‘‘Transparent Electronics’’ has opened 0749-6036/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.spmi.2013.05.006 ⇑ Corresponding author. Tel.: +91 4362 278602, mobile: +91 9443524180; fax: +91 4374 239328. E-mail address: kkr1365@yahoo.com (K. Ravichandran). Superlattices and Microstructures 60 (2013) 327–335 Contents lists available at SciVerse ScienceDirect Superlattices and Microstructures journal homepage: www.elsevier.com/locate/superlattices