Photoluminescence thermal quenching properties of zinc sulfide grown by mist chemical vapor deposition

Abstract

Photoluminescence (PL) thermal quenching properties of zinc sulfide (ZnS) films, which were grown by mist chemical vapor deposition (mist‐CVD), were systematically investigated. The samples were grown from thiourea‐based solutions at various temperatures. Strong PL emissions related to S vacancies were observed from the sample grown at 600 and 700 °C and their thermal quenching properties were very small. PL spectra from the sample grown at 500 °C contains zinc oxide (ZnO) related peaks. The ZnO related PL peaks has almost no energy shift with the increase of temperature. This would be due to the mismatch of thermal expansion coefficient between ZnS and ZnO.

Structural characteristics of a non-polar ZnS layer on a ZnO buffer layer formed on a sapphire substrate by mist chemical vapor deposition

“…[5][6][7][8][9][10][11] Recently, sulfides such as zinc sulfide (ZnS) have been formed via mist-CVD by adding sulfur-containing materials such as thiourea. [12][13][14] ZnS is an abundant material and a wide-bandgap compound semiconductor from group II-VI. Because ZnS has a large exciton binding energy of 37 meV, it is a promising material for use in light-emitting devices with high luminous efficiency.…”

“…15) In addition, it is possible for ZnS to emit blue light via defect levels. 12,16,17) Our ultimate goal is to fabricate low-cost light-emitting diodes (LEDs) with ZnS-based materials using mist-CVD. Gallium nitride (GaN)-based LEDs 18,19) are now widely used as white light sources instead of fluorescent lamps.…”