Chemical Vapor Deposition of Gallium Sulfide Thin Films

Abstract

The compound [Ga(S-i-Pr)2(μ-S-i-Pr)]2, a thermally stable solid with a low melting point, was used as a single-source precursor to gallium sulfide films in a low-pressure chemical vapor deposition process. Film depositions were carried out at substrate temperatures in the range 350−610 °C. The films were determined to have a Ga2S3 stoichiometry by Rutherford backscattering and energy-dispersive X-ray spectrometries. X-ray diffraction studies showed that the films deposited on glass, silicon, and YSZ (111) substrates were composed of γ-Ga2S3, α-Ga2S3, and highly oriented γ-Ga2S3, respectively.

Structural and optical properties of gallium sulfide thin film

“…As we mentioned in the introduction, direct band gap energies of GaS thin films grown by different techniques and under different growth conditions have been reported between 2.55 and 3.6 eV [16][17][18]. Although the direct band gap energy obtained in this study for CBD-grown gallium sulfide film is different from the reported values, it falls in the reported interval and it is close to the band gap energy given for GaS grown by thermal evaporation [18].…”

“…Several deposition techniques were used in the growth of GaS thin films, including microwave glow discharge [15], chemical vapor deposition [16], modulated flux deposition [17], and thermal evaporation [18]. It is known that deposition conditions/techniques may affect the structural, optical, and electrical properties of thin films.…”

“…It is known that deposition conditions/techniques may affect the structural, optical, and electrical properties of thin films. For instance, Suh et al and Sanz et al deposited GaS thin films by using chemical vapor deposition and modulated flux deposition techniques, and they found the direct band gap energies of thin films as 3.47 eV and 3.4 eV, respectively [16,17].…”

Solution based CVD of main group materials

“…68 They also have a potential application as passivating layers for III-V devices and are related to ternary phases, such as CuInE 2 (E = S or Se) with uses in solar cells. 73,74 Examples of precursors to metal chalcogenides have been reviewed. The wurtzite-type hexagonal structures, a-Ga 2 S 3 and b-Ga 2 S 3 , as well as a monoclinic g-Ga 2 S 3 phase exists.…”

Intramolecularly Coordinated Gallium Sulfides: Suitable Single Source Precursors for GaS Thin Films

“…[1] The applicationso fa morphous chalcogenides are based on their specific properties such as broad IR transparency (up to 12 and 16 mmf or sulfides and selenides, respectively), photosensitivity,h igh (non)linear refractive indexes, and low phonon energy (approximately 350 cm À1 for sulfidesa nd about 250 cm À1 for selenides). [6] Barron et al have reportedt he synthesis of cubic GaS by using atmosphericp ressure CVD using [(tBu)GaS] 4 as the SSP. Consequently,r adiative efficiencies of most rare earth ions fluorescence emissions in the near-and mid-IR regions are improved.…”