Transparent Conducting Boron-Doped Zinc Oxide Films Deposited by DC-Magnetron Sputtering in B₂H₆-Ar Mixtures

Abstract

Transparent conducting ZnO:B films for solar cells were produced by DC magnetron sputtering in B 2 H 6 -Ar mixtures. Low-resistivity textured films could be obtained at relatively low substrate temperatures of 150-200° C. The resistivity, electron mobility and carrier concentration were 4×10 -4 Ω cm, 60 cm 2 / Vs and 2×10 20 cm -3 , respectively. The 2-µ m-thick films showed a sheet resistance of 2 Ω/ sq and optical transmission of greater than 85% at wavelengths of 0.6-1.0 µ m. These films exhibited higher optical transmission in the near infrared region than ZnO:Al films with the same resistivity because of high electron mobility. No degradation of resistivity and optical transmission was observed after exposure at 85° C and 95%RH for 5 h.