Elimination of BPD in 5~30um Thick 4H-SiC Epitaxial Layers Grown in a Warm-Wall Planetary Reactor

2016 ◽  
Vol 858 ◽  
pp. 189-192 ◽  
Author(s):  
Gan Feng ◽  
Yong Qiang Sun ◽  
Wei Ning Qian ◽  
Li Ping Lv ◽  
Jian H. Zhao ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Growth Process ◽  
High Efficiency ◽  
Conversion Ratio ◽  
Epitaxial Layers ◽  
Initial Surface ◽  
Surface Conditions

The process of the epitaxial growth of 4H-SiC has been optimized to obtain higher ratio of conversion of BPDs to the TEDs on 100 mm substrates in a warm-wall planetary reactor. 100% BPD conversion ratio was successfully obtained with excellent surface morphology under optimized growth process. The high efficiency of the optimized growth process in BPD conversion is independent of the initial surface conditions and BPD density of the substrates.

Homoepitaxial Growth on Si-Face (0001) On-Axis 4H-SiC Substrates

2019 ◽  
Vol 954 ◽  
pp. 31-34
Author(s):  
Guo Guo Yan ◽  
Xing Fang Liu ◽  
Feng Zhang ◽  
Zhan Wei Shen ◽  
Wan Shun Zhao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Growth Temperature ◽  
Epitaxial Layers ◽  
Homoepitaxial Growth ◽  
Influence Mechanism

Homoepitaxial growths of 4H-SiC were performed on Si-face (0001) on-axis substrates in a SiH4-C2H4-H2-HCl system by using our home-made vertical hot wall CVD reactor. The influence mechanism of the growth temperature and C/Si ratio on the morphology and growth rate was studied. It is found that the steps in the epilayer become more clear with the increasing temperatures. The result indicates that the C/Si ratio window of on-axis epitaxial growth is very narrow. Only when the C/Si ratio was 1.2, a slightly improved surface morphology can be achieved. The results indicate that 4H-SiC epitaxial layers were obtained on on-axis substrates and the films were highly-oriented 4H-SiC.

High Uniformity with Reduced Surface Roughness of Chloride Based CVD Process on 100mm 4° Off-Axis 4H-SiC

2012 ◽  
Vol 717-720 ◽  
pp. 93-96 ◽  
Author(s):  
Hrishikesh Das ◽  
Swapna G. Sunkari ◽  
Timothy Oldham ◽  
Janna R. B. Casady ◽  
Jeff B. Casady
Keyword(s):  
Surface Roughness ◽  
Epitaxial Growth ◽  
Growth Rates ◽  
Growth Process ◽  
Process Conditions ◽  
Epitaxial Layers ◽  
High Uniformity ◽  
Highly Uniform ◽  
Reduced Surface

In this work we present the epitaxial growth of 4H-SiC on 100mm 4° off-axis substrates grown in a multi-wafer CVD planetary reactor. Highly uniform epitaxial layers having thickness and doping uniformities of 1.7% and 1.4% respectively were grown in the production reactor with optimized process conditions at 8µm/hr and 30µm/hr growth rates. Process optimizations resulted in epitaxial layers with surface roughness (RMS) of 0.32nm. Epitaxial layers with a thickness of 53µm grown with a 30µm/hr growth process had minimal degradation in surface roughness (RMS of 0.39nm).

Formation and Reduction of Large Growth Pits on 100 mm 4° 4H-SiC

2016 ◽  
Vol 858 ◽  
pp. 193-196 ◽  
Author(s):  
Yong Qiang Sun ◽  
Gan Feng ◽  
Jun Yong Kang ◽  
Wei Ning Qian ◽  
Li Ping Lv ◽  
...  
Keyword(s):  
Growth Rate ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Process Parameters ◽  
Growth Process ◽  
High Quality ◽  
Substrate Quality ◽  
Large Growth

The large growth pits (LGPs) dependence of substrate quality, growth rate, and C/Si ratio have been discussed in the 4H-SiC epitaxial growth on 100 mm N-type 4H-SiC Si-face substrates misoriented by 4° toward [11-20] with a warm-wall planetary reactor. The formation and reduction of LGPs have been investigated by adjusting the growth process parameters. With the optimized process, the perfect surface morphology with lower LGPs density has been obtained on the high quality substrate.

Epitaxial Growth of n-Type 4H-SiC on 3" Wafers for Power Devices

2005 ◽  
Vol 483-485 ◽  
pp. 141-146 ◽  
Author(s):  
Bernd Thomas ◽  
Christian Hecht
Keyword(s):  
Atomic Force Microscopy ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Crystal Quality ◽  
Process Conditions ◽  
Epitaxial Layers ◽  
Power Devices ◽  
Force Microscopy ◽  
Atomic Force ◽  
In Doping

In this paper we present recent results of epitaxial growth of 4H-SiC on 3” (0001) 8° and 4° off-oriented wafers using a multi-wafer hot-wall CVD system. This equipment exhibits a capacity of 5x3” or 7x2” wafers per run. By optimizing the process conditions epitaxial layers with excellent crystal quality, purity and homogeneity in doping and thickness were grown. The intra-wafer as well as the wafer-to-wafer homogeneity will be illustrated by doping and thickness mappings of a full-loaded run. Surface morphology of epitaxial layers on 8° and 4° off-oriented wafers was investigated by atomic force microscopy.

Conversion of Basal Plane Dislocations to Threading Edge Dislocations in Growth of Epitaxial Layers on 4H-SiC Substrates with a Vicinal Off-Angle

2014 ◽  
Vol 778-780 ◽  
pp. 99-102 ◽  
Author(s):  
Keiko Masumoto ◽  
Sachiko Ito ◽  
Hideto Goto ◽  
Hirotaka Yamaguchi ◽  
Kentaro Tamura ◽  
...  
Keyword(s):  
Epitaxial Growth ◽  
Edge Dislocation ◽  
Basal Plane ◽  
Conversion Ratio ◽  
Epitaxial Layers ◽  
Etch Pits ◽  
X Ray ◽  
Basal Plane Dislocation ◽  
Edge Dislocations ◽  
Koh Etching

We have investigated a conversion of basal plane dislocation (BPD) to threading edge dislocation (TED) in growth of epitaxial layers (epi-layers) on 4H-SiC vicinal substrates with an off-angle of 0.85° at low C/Si ratio of 0.7 by using deep KOH etching and X-ray topography observations. Deep KOH etching indicated that BPDs in the substrates converted to TEDs in the epi-layers. X-ray topography observations suggested that the conversion occurred during epitaxial growth when the thickness of epi-layers was less than 1.5 μm. We found that the conversion ratio obtained from counting deep KOH etch pits was over 99%.

A Designed Experiment Approach to Improvement and Understanding of the SiC Epitaxial Growth Process

2007 ◽  
Vol 556-557 ◽  
pp. 57-60
Author(s):  
James D. Oliver ◽  
Brian H. Ponczak
Keyword(s):  
Epitaxial Growth ◽  
Carrier Concentration ◽  
Layer Thickness ◽  
Process Parameters ◽  
Growth Process ◽  
Epitaxial Layers ◽  
Designed Experiments ◽  
Planetary Rotation ◽  
Designed Experiment ◽  
Resultant Effect

A series of designed experiments have been conducted over a period of years in a multiwafer, planetary rotation, epitaxial reactor to quantify the effects of various epitaxial growth process parameters on the resulting SiC epitaxial layers. This paper summarizes the results obtained through statistically designed experiments varying process parameters and their resultant effect on the layer thickness, carrier concentration and the variability of these parameters wafer-to-wafer, and within a wafer.

New SiC Epitaxial Growth Process with up to 100% BPD to TED Defect Conversion on 150mm Hot-Wall CVD Reactor

2019 ◽  
Vol 963 ◽  
pp. 123-126
Author(s):  
Tobias Höchbauer ◽  
Christian Heidorn ◽  
Nikolaos Tsavdaris
Keyword(s):  
Epitaxial Growth ◽  
Epitaxial Layer ◽  
Basal Plane ◽  
Growth Process ◽  
High Growth ◽  
High Growth Rate ◽  
Layer Growth ◽  
Structural Defects ◽  
Epitaxial Layers ◽  
Basal Plane Dislocation

The future challenges for SiC device technology are cost reduction and increased reliability. A key point to achieve that is the increase of yield during epitaxial layer growth through the reduction of structural defects (such as basal plane dislocations and triangle defects), an increased thickness and doping uniformity, and a high growth rate. Despite significant advancements in SiC epitaxial growth technology, it still constitutes a big challenge to find the optimum working point at which all those requirements are fulfilled. By implementing a new epitaxial layer growth process, we are able to grow basal plane dislocation free epitaxial layers, while the density of other structural defects remains low. Additionally, intra-wafer thickness and doping uniformities of the epitaxial layers are further improved.

Conversion of Basal Plane Dislocations to Threading Edge Dislocations by Annealing 4H-SiC Epilayers at High Temperatures

2013 ◽  
Vol 740-742 ◽  
pp. 601-604
Author(s):  
Xuan Zhang ◽  
Masahiro Nagano ◽  
Hidekazu Tsuchida
Keyword(s):  
Surface Morphology ◽  
Ion Implantation ◽  
Epitaxial Growth ◽  
High Temperatures ◽  
Basal Plane ◽  
Grazing Incidence ◽  
Conversion Ratio ◽  
Prismatic Plane ◽  
X Ray ◽  
Edge Dislocations

Basal plane dislocations (BPDs) converting to threading edge dislocations (TEDs) has been observed in 4H-SiC epilayers after thermal annealing at high temperatures. Grazing incidence reflection synchrotron X-ray topography was used to investigate the dislocation behaviors. It is argued that the conversion is achieved by constricted BPD segments cross-slipping to the prismatic plane and TED glide on its slip plane. Higher conversion ratio and better surface morphology were achieved by performing ion implantation and annealing before epitaxial growth.

Use of Vanadium Doping for Compensated and Semi-Insulating SiC Epitaxial Layers for SiC Device Applications

2012 ◽  
Vol 717-720 ◽  
pp. 133-136 ◽  
Author(s):  
Bharat Krishnan ◽  
Rooban Venkatesh K.G. Thirumalai ◽  
Siva Prasad Kotamraju ◽  
Joseph Neil Merrett ◽  
Yaroslav Koshka
Keyword(s):  
Growth Rate ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Growth Rates ◽  
Reverse Bias ◽  
Epitaxial Layers ◽  
Pin Diodes ◽  
Vanadium Doping ◽  
Device Applications ◽  
Epilayer Surface

Vanadium doping from SiCl4 source during epitaxial growth with chlorinated C and Si precursors was investigated as a mean of achieving compensated and semi-insulating epitaxial 4H-SiC layers for device applications. Thin epilayers were grown at 1450°C with a growth rate of ~6 μm/h. Experiments at 1600°C resulted in the growth rates ranging from 60 to 90 µm/h producing epilayers with thickness above 30 µm. V concentrations up to about 1017cm-3 were found safe for achieving defect-free epilayer surface morphology, however certain degradation of the crystalline quality was detected by XRD at V concentrations as low as 3-5x1015 cm-3. Controllable compensation of nitrogen donors with V acceptors provided low-doped and semi-insulating epitaxial layers. Mesa isolated PiN diodes with V-acceptor-compensated n- epilayers used as drift regions showed qualitatively normal forward- and reverse-bias behavior.

Improvement of Homoepitaxial Layer Quality Grown on 4H-SiС Si-Face Substrate Lower than 1 Degree Off Angle

2012 ◽  
Vol 717-720 ◽  
pp. 141-144 ◽  
Author(s):  
Kazutoshi Kojima ◽  
Satchiko Ito ◽  
Akiyo Nagata ◽  
Hajime Okumura
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Schottky Barrier ◽  
Epitaxial Layer ◽  
Flow Rate ◽  
Growth Process ◽  
High Yield ◽  
Schottky Barrier Diodes ◽  
Specular Surface ◽  
Interfacial Dislocations

In this study, we struck a balance between specular surface morphology and polytype homogeneity on an epitaxial layer grown on 4H-SiC Si-face substrate with off angle less than 1degree by controlling the C/Si ratio with the SiH4 flow rate. Schottky barrier diodes fabricated on a grown epitaxial layer exhibited a blocking of voltage over 1000 V and an n value of less than 1.1 with a high yield of more than 80%. A substrate with a low off angle was found to have an advantage as regareds the stress that generates the interfacial dislocations at the epitaxial layer/substrate interface during the epitaxial growth process.

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