Electrical properties of p-type ZnTe thin films by immersion in Cu solution

• Published in: Materials letters 2014-07, Vol.126, p.271-273
• Main Authors: Lastra, G., Luque, P.A., Quevedo-Lopez, M.A., Olivas, A.
• Format: Article
• Language: English
• Subjects: Bias; Contact resistance; Cu doping; Deposition; Diffraction; Dopes; Semiconductor devices; Thin films; Thin-film transistor; Zinc tellurides; ZnTe
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2014.04.058

ZnTe thin films were deposited on SiO2 substrate by pulsed-laser deposition (PLD) at room temperature. The ZnTe films were immersed in different concentrations of Cu(NO3)2–3H2O solutions for 1min, then heated at 200 and 300°C, both temperatures for 10min in a N2 atmosphere. The X-ray diffraction (XRD) showed the hexagonal and orthorhombic ZnTe phases when the copper-doped films were heated at 200 and 300°C for 10min respectively. The films immersed in 15 and 60mg of Cu(NO3)2–H2O solutions had similar values of sheet resistance ~104Ω/□, resistivity ~10−1Ωcm, specific contact resistance ~10−4Ωcm2, and hall mobility 5cm2/Vs. Also, the copper-doped conditions were used to dope the source and drain bias to make a thin-film transistor of ZnTe (TFT) by photolithography. ZnTe TFT by photolithography. Variation of the (a) sheet resistance and (b) resistivity, when the mg of Cu(NO3)2–3H2O is increased. [Display omitted] •The sheet resistance of the undoped ZnTe decreased from 2.52×1010 to 3.92×104Ω/□ when the films were immersed in 15mg of Cu(NO3)2–3H2O solution.•The resistivity of the undoped ZnTe decreased from 2.26×105 to 3.50×10−1Ωcm when the films were immersed in 15mg of Cu(NO3)2–3H2O solution.•The p-type ZnTe thin films doped with 15 and 60mg of Cu(NO3)2–H2O solutions had similar values of sheet resistance, resistivity, specific contact resistance, and hall mobility.•The X-ray diffraction (XRD) showed the hexagonal and orthorhombic ZnTe phases.•The hole mobility of the ZnTe TFT immersed in 15mg of Cu(NO3)2–H2O solution was 1×10−2cm2/Vs.