A model for carbon incorporation from trimethyl gallium in chemical vapor deposition of gallium nitride

Carbon doping during CVD of GaN semiconductor materials is modeled using ab initio quantum chemical calculations and computational fluid dynamics.

Effect of Temperature on GaN Films Deposited on Diamond Substrate Using an ECR-PEMOCVD

Highly-quality GaN films were deposited on diamond substrate using an electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition system (ECR-PEMOCVD) at the proper temperature. The source of gallium is Trimethyl gallium (TMGa) and N2, and the influence of temperature on the properties of GaN films was investigated systematically by X-ray diffraction analysis (XRD), atomic force microscopy (AFM), room temperature photoluminescence (PL), respectively. The dense and uniformed GaN films with highly c-axis preferred orientation were successfully achieved on free-standing diamond substrates under optimized deposition temperature of 400 °C.

Influence of TMGa Flux on the Improvement of GaN Films on Thick Freestanding Diamond Films

High-quality GaN films are deposited on diamond films using an electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition (ECR-PEMOCVD) under the condition of the proper Trimethyl gallium (TMGa) flux. The influence of TMGa flux on the properties of GaN films is systematically investigated by x-ray diffraction analysis (XRD) and atomic force microscopy (AFM). The results show that the high quality GaN films with small surface roughness and high c-orientation are successfully achieved at the optimized flux. The most significant improvements in morphological and structural properties of GaN films are obtained by using a proper TMGa flux

Characterization of Defects in Gallium Nitride Thin Films by SEM

Gallium nitride (GaN) thin films samples were grown by metal-organic chemical vapor deposition (MOCVD) with ammonia and trimethyl-gallium, and the samples were annealed rapidly at different temperature. The scanning electron microscope (SEM) analysis was employed to study the surface morphology and lattice defects of the GaN thin films. The surface morphology of the thin films prepared at different condition was uniform and smoothly. The relationship of the films defects and the annealed temperature were summarized.

EFFECTS OF OPERATING CONDITIONS ON THE DEPOSITION OF GaAs IN A VERTICAL CVD REACTOR

A numerical study is needed to gain insight into the growth mechanism and improve the reactor design or optimize the deposition condition in chemical vapor deposition (CVD). In this study, we have performed a numerical analysis of the deposition of gallium arsenide ( GaAs ) from trimethyl gallium (TMG) and arsine in a vertical CVD reactor. The effects of operating parameters, such as the rotation velocity of susceptor, inlet velocity, and inlet TMG fraction, are investigated and presented. The three-dimensional model which is used in this investigation includes complete coupling between the thermal-fluid transport and species transport with chemical reaction.

Gallium Nitride Growth Using Diethylgallium Chloride as an Alternative Gallium Source

Metal organic vapor phase epitaxy (MOVPE) of GaN has been carried out using diethyl gallium chloride (DEGaCl) and ammonia. The growth rate and efficiency of the DEGaCl-based growth decreases with increasing temperature when compared to trimethyl gallium (TMG)-based growth under similar conditions. Both low temperature buffer and the high temperature GaN layers were grown using the DEGaCl-NH3 precursor combination on the basal plane of sapphire and compared to similar structures grown using TMG and NH3. DEGaCl-based growth reveals an improved growth behavior under identical growth conditions to the conventional TMGa and ammonia growth. X-ray, Hall, and atomic force microscopy (AFM) measurements have been carried out on these samples providing a direct comparison of materials properties associated with these growth precursors. For the DEGaCl-based growth, the x-ray rocking curve line width, using the (0002) reflection, is as low as 300 arcsec on a 2.5-micron thick film. A RMS surface roughness of ∼0.5nm measured over a 10×10 micron area.

Gallium Nitride Growth Using Diethylgallium Chloride as an Alternative Gallium Source

Metal organic vapor phase epitaxy (MOVPE) of GaN has been carried out using diethyl gallium chloride (DEGaCI) and ammonia. The growth rate and efficiency of the DEGaCl-based growth decreases with increasing temperature when compared to trimethyl gallium (TMG)-based growth under similar conditions. Both low temperature buffer and the high temperature GaN layers were grown using the DEGaCI-NH3 precursor combination on the basal plane of sapphire and compared to similar structures grown using TMG and NH3. DEGaCl-based growth reveals an improved growth behavior under identical growth conditions to the conventional TMGa and ammonia growth. X-ray, Hall, and atomic force microscopy (AFM) measurements have been carried out on these samples providing a direct comparison of materials properties associated with these growth precursors. For the DEGaCl-based growth, the x-ray rocking curve line width, using the (0002) reflection, is as low as 300 arcsec on a 2.5-micron thick film. A RMS surface roughness of ∼0.5nm measured over a 10x10 micron area.