Wide bandgap engineering of (GaIn)2O3 films

Lower temperature growth of single phase MgZnO films in all Mg content range

“…Similar results have been reported for the MgZnO films obtained by sputtering growth technique [10,11]. Pulsed laser deposition (PLD) is an effective growth method for fabricating such metastable phase films due to the relative high kinetic energies that the ablated species have [12][13][14]. Using this method, Ohtomo et al have succeeded in growing single phase wurtzite MgZnO films with Mg content up to 0.33 [15].…”

Atomic signatures of local environment from core-level spectroscopy inβ−Ga2O3

“…With its band gap of about 4.8 eV [5] and its remarkably high carrier mobility [8], it is considered an excellent candidate for the new generation of opto-electronic devices. These properties can be further engineered by forming ternary compounds, upon inclusion of e.g., indium atoms [9]. In order to achieve full control in tailoring these materials with increasing level of complexity, it is necessary to rigorously characterize and fully understand the features of the pristine systems.…”

Toward the understanding of annealing effects on (GaIn)2O3 films

“…The transmission spectra of the annealed (GaIn) 2 O 3 films indicate: 1) transmittances of all samples in visible and infrared region above 85%, 2) a sharp absorption edge for all (GaIn) 2 O 3 alloy films caused by the fundamental absorption of light, and 3) shift of the absorption edge to lower wavelength with increase in nominal indium content. Recently, we demonstrated that the bandgap of (GaIn) 2 O 3 films can be tailored between 3.8 eV and 5.1 eV by controlling the indium content [4]. Unfortunately the transmittance of the films grown at 500°C with nominal indium content from 0.2 to 0.7 was not high due to phase separation.…”

“…However phase separation still appeared when indium content was between 0.08 and 0.67. We also found that although the indium content of (GaIn) 2 O 3 films measured by energy dispersive X-ray spectroscopy can be controlled by the element composition in the targets, and the bandgap of (GaIn) 2 O 3 films can be tailored between 3.8 eV and 5.1 eV, the phase separation was observed for the films with nominal indium content (weight ratio of In/(Ga + In) in target) ranging from 0.2 to 0.5 (indium content in (GaIn) 2 O 3 films ranging from 0.18 to 0.33) [4]. Fortunately, further research found that by annealing the film (nominal indium content of 0.3) deposited at room temperature in air ambient, high quality β-(GaIn) 2 O 3 film (with indium content of 0.2 in the film) without phase separation can be obtained [9].…”

“…(GaIn) 2 O 3 alloys are desirable for these applications as they enable a tunable wide bandgap across the composition range, which spans 3.6 eV in In 2 O 3 to 5.1 eV in Ga 2 O 3 [2][3][4]. The structure of (GaIn) 2 O 3 alloys can be that of either β-Ga 2 O 3 or cubic In 2 O 3 , depending on the Ga/In ratio in it [3,[5][6][7].…”