Abstract
By investigating the influence of key growth variables on the measured structural and electrical properties of SnO2 prepared by pulsed laser deposition (PLD) we demonstrate fine control of intrinsic n-type defect formation. Variation of growth temperatures shows oxygen vacancies (V-O) as the dominant defect which can be compensated for by thermal oxidation at temperatures >500 degrees C. As a consequence films with carrier concentrations in the range 10(16)-10(19) cm(-3) can be prepared by adjusting temperature alone. By altering the background oxygen pressure (P-D) we observe a change in the dominant defect - from tin interstitials (Sn-i) at low P-D (<50 mTorr) to V-O at higher P-D with similar ranges of carrier concentrations observed. Finally, we demonstrate the importance of controlling the composition target surface used for PLD by exposing a target to >100000 laser pulses. Here carrier concentrations >1 x 10(20) cm(-3) are observed that are associated with high concentrations of Sn-i which cannot be completely compensated for by modifying the growth parameters.