Structural and Optical Properties of Indium Selenide (InSe) Thin Films Deposited on Glass and GaSe Single Crystal Substrates by SILAR Method

Abstract

Structural, morphological and optical properties of undoped and boron doped Indium Selenide (InSe) thin films grown on glass and layered Gallium Selenide (GaSe) single crystal substrates with SILAR method have been investigated by XRD, AFM and UV-Vis spectrophotometer techniques. XRD measurements showed that the crystal structure of InSe thin films grown on glass substrates were hexagonal P61 γ-In2Se3 with lattice parameters a=7.1286 Å, c=19.382 Å and z=6 while the InSe thin films grew as hexagonal P63/mmc InSe with lattice parameters a=4.005 Å, c=16.640 Å and z=4 on GaSe single crystal substrates. The AFM images showed that average particle sizes of undoped and boron doped InSe thin films were found to be varying between 26.5-60.2 nm and 30.9-101.5 nm grown on glass and GaSe single crystal substrates, respectively. The optical absorption spectra of undoped and boron doped InSe thin films grown on both glass and GaSe single crystal substrates showed absorption maxima around the 2.00 and 2.24 eV, respectively. The calculated Urbach energies of the InSe thin films grown on glass substrates were found bigger than those of the InSe thin films grown on GaSe single crystal substrates.

Recent Advances in the Growth and Characterizations of SILAR-Deposited Thin Films

“…The deposition of Ag 2 S (silver sulfide) films took place on glass slides by using a complexing agent (ammonia (NH 3 )) at 40 • C [17]. Films showed monoclinic phases and preferred orientations corresponding to the (120) plane. Improvements in crystallinity and the red shift in absorption edge could be observed when the deposition cycle increased from 20 to 50 cycles.…”

“…The indium selenide (InSe) films were deposited onto glass substrates (75 cycles) and gallium selenide (GaSe) single crystal substrates (50 cycles), respectively, by using indium (III) sulfate (In 2 (SO 4 ) 3 ) and Na 2 SeSO 3 solution [120]. The XRD studies revealed the hexagonal phase and lattice parameters, such as a = 7.128 Å, c = 19.382 Å, z = 6 for the films grown on glass.…”

“…The boron-doped indium selenide (InSe) films were deposited on different substrates [120]. The XRD analysis showed a broad bump because of the glass substrate, and the intensities of the peaks reduced with the boron addition.…”