Effect of Melt-Back Process on the Quality of Grown Crystal in SiC Solution Growth

2019 ◽  
Vol 963 ◽  
pp. 75-79 ◽  
Author(s):  
Kotaro Kawaguchi ◽  
Kazuaki Seki ◽  
Kazuhiko Kusunoki
Keyword(s):  
Dislocation Density ◽  
Grown Crystal ◽  
Early Stage ◽  
Seed Crystal ◽  
Solution Growth ◽  
Crystal Quality ◽  
Top Seeded Solution Growth ◽  
Koh Etching

We investigated the effect of a melt-back process on the quality of the grown crystal in 4H-SiC solution growth. In our experiments, the crystal was grown by top-seeded solution growth (TSSG) method with and without melt-back, following which the quality of the obtained crystals was compared. When solution growth was carried out without melt-back, solvent inclusions and a different polytype were observed. When molten KOH etching was conducted, the dislocation density in the crystals at the early stage of growth became much higher than that in a seed crystal. Solvent inclusions, a different polytype, and an increase in dislocations were suppressed when solution growth was performed with melt-back. It was confirmed that melt-back is necessary to prevent the deterioration of crystal quality at the early stage of solution growth.

Crystalline Quality Evaluation of 6H-SiC Bulk Crystals Grown from Si-Ti-C Ternary Solution

2005 ◽  
Vol 483-485 ◽  
pp. 13-16 ◽  
Author(s):  
Kazuhiko Kusunoki ◽  
Kazuhito Kamei ◽  
Y. Ueda ◽  
S. Naga ◽  
Y. Ito ◽  
...  
Keyword(s):  
Grown Crystal ◽  
Seed Crystal ◽  
Solution Growth ◽  
Crystalline Quality ◽  
Ternary Solution ◽  
Bulk Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Koh Etching

The growth of 6H-SiC crystal from Si-Ti-C ternary solution was conducted under the temperature gradient and the crystalline quality evaluations of the grown crystals were carried out. 6H-SiC(0001) on-axis pvt-grown crystal was used as a seed crystal. Micropipes in the seed crystal were terminated during the solution growth and 28mm􀊷28mm self-standing micropipe-free SiC crystals were obtained. The quality of the grown crystals was investigated by SIMS, high-resolution x-ray diffraction and molten KOH etching. The content of residual impurities in the SiC were very low. The X-ray 􀐢-rocking curves of the solution grown SiC showed single peak with high peak intensity ,while that of the seed crystal showed several peaks due to the misoriented domains. Moreover, it was found that the number of etch-pit in the grown crystal is much less than that in the seed crystal and it decreases with the increase of the growth thickness. These results indicate that the crystalline quality of grown crystal was significantly improved during the solution growth.

Polytype and Crystal Quality of SiC Crystals Grown on 3C-SiC by Seeded Solution Method

2009 ◽  
Vol 615-617 ◽  
pp. 27-30 ◽  
Author(s):  
Kazuaki Seki ◽  
Ryo Tanaka ◽  
Toru Ujihara ◽  
Yoshikazu Takeda
Keyword(s):  
Growth Process ◽  
Solution Method ◽  
Grown Crystal ◽  
Stacking Faults ◽  
High Density ◽  
Seed Crystal ◽  
Solution Growth ◽  
Crystal Quality ◽  
Seed Crystals

We investigated the effects of the solution growth process on the polytype and crystal quality of the crystals grown on (111) 3C-SiC seed crystals. In spite of the use of 3C-SiC seed crystals, the polytype of the grown crystal changed from 3C-SiC to 6H-SiC, because the stacking errors easily occur due to the similarity of the (111) face of 3C-SiC and the (0001) face of 6H-SiC. Moreover, the grown 6H-SiC crystal affected the crystal quality of the seed crystal, i.e., high-density stacking faults were induced in the seed crystal after the growth process.

Development of Solvent Inclusion Free 4H-SiC Off-Axis Wafer Grown by the Top-Seeded Solution Growth Technique

2018 ◽  
Vol 924 ◽  
pp. 31-34 ◽  
Author(s):  
Kazuhiko Kusunoki ◽  
Kazuaki Seki ◽  
Yutaka Kishida ◽  
Hiroshi Kaido ◽  
Koji Moriguchi ◽  
...  
Keyword(s):  
Grown Crystal ◽  
Crystal Defects ◽  
Solution Growth ◽  
Technological Problem ◽  
Growth Technique ◽  
Basal Plane Dislocation ◽  
Growth Method ◽  
Top Seeded Solution Growth ◽  
Solution Growth Technique

This study reports our newly developed technology for SiC solution growth. In particular, we succeed in completely suppressing solvent inclusions, which have been a serious technological problem peculiar to the solution growth method. Then, we fabricate two-inch-diameter 4° off-axis SiC wafers without solvent inclusions. Moreover, we performed their crystal defects evaluation. It was found that our wafers were low resistance n-type 4H-SiC and contain almost no basal plane dislocation. As a result, the superior quality of our solution-grown crystal was confirmed.

Trials of Solution Growth of Dislocation-Free 4H-SiC Bulk Crystals

2016 ◽  
Vol 858 ◽  
pp. 19-22 ◽  
Author(s):  
Katsunori Danno ◽  
Satoshi Yamaguchi ◽  
Hiroyuki Kimoto ◽  
Kazuaki Sato ◽  
Takeshi Bessho
Keyword(s):  
Dislocation Density ◽  
Grown Crystal ◽  
Seed Crystal ◽  
Solution Growth ◽  
Growth Surface ◽  
Threading Dislocation ◽  
Bulk Crystals ◽  
Low Dislocation Density ◽  
Crystal Diameter ◽  
Growth Dislocation

Solution growth of high-quality 4H-SiC bulk crystals has been performed by using Si-Cr based melt at 2000°C. Through enlargement of crystal diameter which is controlled by meniscus height during growth, dislocation free area has been successfully obtained on the periphery of the crystal. However, the threading dislocations in the seed crystal have penetrated into the grown crystal and have been located around the center of the crystal. To reduce dislocation density in the grown crystals, we have used threading-dislocation-free seedcrystals prepared by solution growth on (1-100). The solution growth on the seed crystal sliced from the (1-100) crystal has resulted in very low dislocation density of grown crystals. In an area of 16 mm2 for the growth surface, no dislocation has been detected.

Improvement of Surface Morphology by Solution Flow Control in Solution Growth of SiC on Off-Axis Seeds

2015 ◽  
Vol 821-823 ◽  
pp. 31-34 ◽  
Author(s):  
Tomonori Umezaki ◽  
Daiki Koike ◽  
S. Harada ◽  
Toru Ujihara
Keyword(s):  
Flow Direction ◽  
Seed Crystal ◽  
Solution Growth ◽  
Rotational Axis ◽  
Solution Flow ◽  
Step Flow ◽  
Unidirectional Flow ◽  
Novel Method ◽  
Set Up ◽  
Top Seeded Solution Growth

The solution growth of SiC on an off-axis seed is effective on the reduction of threading dislocations. We proposed a novel method to grow a SiC crystal on an off-axis seed by top-seeded solution growth (TSSG). In our previous study, a unidirectional solution flow above a seed crystal is effective to suppress surface roughness in the growth on the off-axis seed. However, it is difficult to apply the unidirectional flow in an axisymmetric TSSG set-up. In this study, the unidirectional flow could be achieved by shifting the rotational axis away from the center of the seed crystal. As a result, the smooth surface was obtained in the wider area where the solution flow direction was opposite to the step-flow direction.

Solution Growth and Crystallinity Characterization of Bulk 6H-SiC

2010 ◽  
Vol 645-648 ◽  
pp. 33-36 ◽  
Author(s):  
Nobuyoshi Yashiro ◽  
Kazuhiko Kusunoki ◽  
Kazuhito Kamei ◽  
Akihiro Yauchi
Keyword(s):  
Grown Crystal ◽  
Solution Growth ◽  
Growth Technique ◽  
Rocking Curve ◽  
Long Time ◽  
Crystal Seed ◽  
Koh Etching ◽  
Light Green ◽  
Solution Growth Technique

The stable long time growth with the use of Si -C-Ti ternary solution was realized　by improving the thermal condition during the growth. We have succeeded in obtaining a maximum 10 mm thick bulk 6H-SiC crystal, which is the largest bulk crystal ever obtained by the solution growth technique. The obtained crystal was free of cracks and exhibited a homogeneous light green color. The crystallinity of the grown crystal was characterized by X-ray rocking curve measurements using (0006) reflection and by the molten KOH etching. The mapping of the full width at half maximum (FWHM) revealed the average FWHM around 30 arc seconds and the minimal FWHM under 16 arc seconds. The etch pit density (EPD) was typically in the range between 104 and 105 cm-2, which was comparable to that of the crystal seed.

Solution Growth of 3C-SiC on 6H-SiC Using Si Solvent under N2-He Atmosphere

2008 ◽  
Vol 600-603 ◽  
pp. 187-190 ◽  
Author(s):  
Kazuhiko Kusunoki ◽  
Kazuhito Kamei ◽  
Nobuyoshi Yashiro ◽  
Takashi Tanaka ◽  
Akihiro Yauchi
Keyword(s):  
Growth Temperature ◽  
The Other ◽  
Solution Growth ◽  
Epitaxial Layers ◽  
Other Hand ◽  
Homoepitaxial Layers ◽  
Top Seeded Solution Growth ◽  
Koh Etching

Top seeded solution growth of SiC on on-axis 6H-SiC was performed using Si solvent at growth temperature as high as 1645-1870°C. It was found that different polytypes of SiC layers were grown on 6H-SiC depending on gas species during growth. The growth under He atmosphere produced 6H-SiC homoepitaxial layers. On the other hand, the growth under N2-He atmosphere led to 3C-SiC epitaxial layers. It was obvious that the nitrogen dissolved in solvent strongly favoured the 3C-SiC polytype formation on 6H-SiC. We also conducted characterization of 3C-SiC layers grown on 6H-SiC (0001)Si by TEM, molten KOH etching and precise XRD measurement.

High Temperature Solution Growth on Free-Standing (001) 3C-SiC Epilayers

2009 ◽  
Vol 615-617 ◽  
pp. 37-40 ◽  
Author(s):  
Ryo Tanaka ◽  
Kazuaki Seki ◽  
Toru Ujihara ◽  
Yoshikazu Takeda
Keyword(s):  
Grown Crystal ◽  
Stacking Faults ◽  
Seed Crystal ◽  
Solution Growth ◽  
High Temperature Solution ◽  
Si Substrate ◽  
Free Standing ◽  
Cvd Method ◽  
Temperature Solution ◽  
Cvd Growth

Solution growth was performed using a free-standing (001) 3C-SiC epilayer as a seed crystal at a growth temperature of 1700°C. The seed crystal was prepared by a CVD method on the undulated Si substrate. 3C-SiC stably grew on the (001) seed crystal. However, dark stripes from the seed crystal to the grown crystal along {111} planes were clearly observed. The stripes were due to the high-density stacking faults extended from the stacking faults in the 3C-SiC epilayer that were induced during the CVD growth on Si substrate.

Top-Seeded Solution Growth of 4H-SiC Bulk Crystal Using Si-Cr Based Melt

2012 ◽  
Vol 717-720 ◽  
pp. 61-64 ◽  
Author(s):  
Hironori Daikoku ◽  
M. Kado ◽  
H. Sakamoto ◽  
Hiroshi Suzuki ◽  
T. Bessho ◽  
...  
Keyword(s):  
Growth Rate ◽  
Seed Crystal ◽  
Solution Growth ◽  
Bulk Crystals ◽  
High Quality ◽  
Cross Sectional ◽  
Formation Technique ◽  
Top Seeded Solution Growth ◽  
Microscopy Images

We have grown high-quality long cylindrical (12 mm thick) 4H-SiC bulk crystals by the meniscus formation technique, which was first applied for the solution growth of bulk SiC. It enabled long-term growth by suppressing parasitic reactions such as polycrystal precipitation around the seed crystal. In addition, we could control the growth angle from −22° to 61° by adjusting the meniscus height. The thickness of the grown cylindrical crystals was 12 mm, which is the largest reported until now, and corresponded to a growth rate of 0.6 mm/h. Smooth morphology growth was maintained on the (000-1) C-face. In cross-sectional transmission optical microscopy images, few solvent inclusions and voids were observed. XRD measurements revealed that the FWHM values of the grown crystals were almost the same as those of the seed crystal.

Sign in / Sign up

Export Citation Format

Share Document