Control of the Growth Habit in the Na Flux Growth of GaN Single Crystals

2012 ◽  
Vol 717-720 ◽  
pp. 1291-1294 ◽  
Author(s):  
Mamoru Imade ◽  
Yusuke Konishi ◽  
Hideo Takazawa ◽  
Kosuke Murakami ◽  
Hiroki Imabayashi ◽  
...  

Seeded growth of gallium nitride (GaN) crystals on a spontaneously nucleated small GaN by the Na flux method was performed. In this study, we attempted to control the growth habit by changing the flux composition (Ga/Na) and by introducing a small amount of additives (Ca and Li). Our experiment clarified that a low Ga composition was preferred to grow high-crystallinity prismatic GaN crystals with a high growth rate. Furthermore, the transparent GaN single crystals with prism shape could be grown by the addition of Ca and Li.

2010 ◽  
Vol 645-648 ◽  
pp. 63-66 ◽  
Author(s):  
Guoli L. Sun ◽  
Irina G. Galben-Sandulache ◽  
Thierry Ouisse ◽  
Jean Marc Dedulle ◽  
Michel Pons ◽  
...  

The Continuous Feed-Physical Vapor Transport Technique (CF-PVT) was optimized by considering the heating, thermal insulation and the geometry of growth cavity. The effects of seeds on the surface morphology of the grown layer have been discussed. We successfully grew 3C-SiC bulk with a diameter of 7.0 mm and 3.3 mm in height with a high growth rate of 0.8 mm/h by the CF-PVT technique.


2008 ◽  
Vol 600-603 ◽  
pp. 191-194
Author(s):  
Takashi Tanaka ◽  
Nobuyoshi Yashiro ◽  
Kazuhiko Kusunoki ◽  
Kazuhito Kamei ◽  
Akihiro Yauchi

We have successfully grown 3C-SiC(111) single crystals 10mm x 10mm in dimension on 6H-SiC(0001) substrate by the solution growth method using cold crucible technique. The growth rate of 60μm/hr was achieved. The use of Si-Ti-C ternary solution as well as the electromagnetic stirring are responsible for the relatively high growth rate in solution method. The threading dislocation density is low and the etch pit density amounts to 105-106 /cm2 at the lowest region. Polytype of the grown layer has changed from 3C to 6H with an increase in the dip depth of substrate. A mathematical model was applied to get better understanding of what happened in the crucible.


2013 ◽  
Vol 740-742 ◽  
pp. 323-326
Author(s):  
Kassem Alassaad ◽  
François Cauwet ◽  
Davy Carole ◽  
Véronique Soulière ◽  
Gabriel Ferro

Abstract. In this paper, conditions for obtaining high growth rate during epitaxial growth of SiC by vapor-liquid-solid mechanism are investigated. The alloys studied were Ge-Si, Al-Si and Al-Ge-Si with various compositions. Temperature was varied between 1100 and 1300°C and the carbon precursor was either propane or methane. The variation of layers thickness was studied at low and high precursor partial pressure. It was found that growth rates obtained with both methane and propane are rather similar at low precursor partial pressures. However, when using Ge based melts, the use of high propane flux leads to the formation of a SiC crust on top of the liquid, which limits the growth by VLS. But when methane is used, even at extremely high flux (up to 100 sccm), no crust could be detected on top of the liquid while the deposit thickness was still rather small (between 1.12 μm and 1.30 μm). When using Al-Si alloys, no crust was also observed under 100 sccm methane but the thickness was as high as 11.5 µm after 30 min growth. It is proposed that the upper limitation of VLS growth rate depends mainly on C solubility of the liquid phase.


2008 ◽  
Vol 600-603 ◽  
pp. 115-118 ◽  
Author(s):  
Henrik Pedersen ◽  
Stefano Leone ◽  
Anne Henry ◽  
Franziska Christine Beyer ◽  
Vanya Darakchieva ◽  
...  

The chlorinated precursor methyltrichlorosilane (MTS), CH3SiCl3, has been used to grow epitaxial layers of 4H-SiC in a hot wall CVD reactor, with growth rates as high as 170 µm/h at 1600°C. Since MTS contains both silicon and carbon, with the C/Si ratio 1, MTS was used both as single precursor and mixed with silane or ethylene to study the effect of the C/Si and Cl/Si ratios on growth rate and doping of the epitaxial layers. When using only MTS as precursor, the growth rate showed a linear dependence on the MTS molar fraction in the reactor up to about 100 µm/h. The growth rate dropped for C/Si < 1 but was constant for C/Si > 1. Further, the growth rate decreased with lower Cl/Si ratio.


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