In Situ Doping of 3C-SiC Grown on (0001) Sapphire Substrates by LPCVD

2002 ◽  
Vol 389-393 ◽  
pp. 339-342 ◽  
Author(s):  
Guo Sheng Sun ◽  
M.C. Luo ◽  
Lei Wang ◽  
S.R. Zhu ◽  
Jin Min Li ◽  
...  
Keyword(s):  
Sapphire Substrates

Hetero-Epitaxy of Group Va Metals on Sapphire

1972 ◽  
Vol 30 ◽  
pp. 492-493
Author(s):  
J. E. O'Neal ◽  
J. J. Bellina ◽  
B. B. Rath
Keyword(s):  
Thermal Contact ◽  
High Vacuum ◽  
Electron Beam Evaporation ◽  
Ultra High Vacuum ◽  
Backing Plate ◽  
Sapphire Substrates ◽  
Deposition Parameters ◽  
Polishing Damage ◽  
Reflection Electron Diffraction

Thin films of the bcc metals vanadium, niobium and tantalum were epitaxially grown on (0001) and sapphire substrates. Prior to deposition, the mechanical polishing damage on the substrates was removed by an in-situ etch. The metal films were deposited by electron-beam evaporation in ultra-high vacuum. The substrates were heated by thermal contact with an electron-bombarded backing plate. The deposition parameters are summarized in Table 1.The films were replicated and examined by electron microscopy and their crystallographic orientation and texture were determined by reflection electron diffraction. Verneuil-grown and Czochralskigrown sapphire substrates of both orientations were employed for each evaporation. The orientation of the metal deposit was not affected by either increasing the density of sub-grain boundaries by about a factor of ten or decreasing the deposition rate by a factor of two. The results on growth epitaxy are summarized in Tables 2 and 3.

scholarly journals Suppressing the Initial Growth of Sidewall GaN by Modifying Micron-Sized Patterned Sapphire Substrate with H3PO4-Based Etchant

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 622 ◽  
Author(s):  
Wen-Yang Hsu ◽  
Yuan-Chi Lian ◽  
Pei-Yu Wu ◽  
Wei-Min Yong ◽  
Jinn-Kong Sheu ◽  
...  
Keyword(s):  
Sapphire Substrate ◽  
Light Emitting Diodes ◽  
Ex Situ ◽  
Initial Growth ◽  
Patterned Sapphire Substrate ◽  
Light Emitting ◽  
Sapphire Substrates ◽  
Patterned Sapphire Substrates

Micron-sized patterned sapphire substrates (PSS) are used to improve the performance of GaN-based light-emitting diodes (LEDs). However, the growth of GaN is initiated not only from the bottom c-plane but also from the sidewall of the micron-sized patterns. Therefore, the coalescence of these GaN crystals creates irregular voids. In this study, two kinds of nucleation layers (NL)—ex-situ AlN NL and in-situ GaN NL—were used, and the growth of sidewall GaN was successfully suppressed in both systems by modifying the micron-sized PSS surface.

MOVPE growth and in situ characterization of GaN layers on sapphire substrates

2004 ◽  
Vol 201 (2) ◽  
pp. 312-319 ◽  
Author(s):  
H. Hardtdegen ◽  
N. Kaluza ◽  
R. Schmidt ◽  
R. Steins ◽  
E. V. Yakovlev ◽  
...  
Keyword(s):  
In Situ Characterization ◽  
Sapphire Substrates ◽  
Movpe Growth

Growth of (0001) ZnO Thin Films on Sapphire

1996 ◽  
Vol 449 ◽  
Author(s):  
A. J. Drehman ◽  
P. W. Yip
Keyword(s):  
Surface Roughness ◽  
Buffer Layers ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Axis Orientation ◽  
Force Microscopy ◽  
Sapphire Substrates ◽  
Atomic Force

ABSTRACTUsing reactive rf sputtering, we have grown (0001) oriented ZnO films in situ on heated c-axis sapphire substrates, that are promising, particularly in terms of surface roughness, as buffer layers for the subsequent epitaxial growth of III-V nitride films. We compare the effects of on-axis and off-axis sputter geometries on the film epitaxy and smoothness. We also examined the effect of substrate temperature on the growth and smoothness and quality of the film. X-ray diffraction was used to verify the hexagonal ZnO phase, its c-axis orientation and, qualitatively, the degree of its epitaxy. Atomic Force Microscopy (AFM) was used to determine the ZnO growth morphology and roughness. Our best films, obtained by off-axis sputter deposition, have a surface roughness of less than 1 nm.

High-Mobility Ga-Polarity GaN achieved by NH3-MBE

2002 ◽  
Vol 743 ◽  
Author(s):  
J. X. Wang ◽  
X. L. Wang ◽  
D. Z. Sun ◽  
J. M. Li ◽  
Y. P. Zeng ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Mobility ◽  
Radio Frequency Plasma ◽  
Chemical Solution ◽  
High Quality ◽  
Sapphire Substrates ◽  
Best Value ◽  
Frequency Plasma ◽  
Surface Examination

ABSTRACTGaN epilayers were grown on (0001) sapphire substrates by NH3-MBE and RF-MBE (radio frequency plasma). The polarities of the epilayers were investigated by in-situ RHEED, chemical solution etching and AFM surface examination. By using a RF-MBE grown GaN layer as template to deposit GaN epilayer by NH3-MBE method, we found that not only Ga-polarity GaN films were repeatedly obtained, but also the electron mobility of these Ga-polarity films was significantly improved with a best value of 290 cm2/V.s at room temperature. Experimental results show it is an easy and stable way for growth of high quality Ga-polarity GaN films.

Schottky I-V Characteristics of Au/Ni/GaN/SiNx nanonework/sapphire structures

2006 ◽  
Vol 955 ◽  
Author(s):  
Jinqiao Xie ◽  
Yi Fu ◽  
Hadis Morkoç
Keyword(s):  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Schottky Diodes ◽  
Chemical Vapor ◽  
Rocking Curve ◽  
X Ray ◽  
Sapphire Substrates ◽  
Control Samples

ABSTRACTGaN layers on sapphire substrates were grown by metalorganic chemical vapor deposition using in situ porous SiNx nano-network. Crystalline quality of epilayers was characterized by X-ray rocking curve scans, and the full width at hall maximum values for (002) and (102) diffractions were improved from 252 arc sec and 405 arc sec, respectively, in control samples to 216 arc sec and 196 arc sec when SiNx was used. Ni/Au Schottky diodes (SDs) were fabricated and the SD performance was found to be critically dependent on the SiNx coverage (fewer and farther the pores the better the results) which is consistent with the trends of XRD and photoluminescence data. A 1.13eV barrier height was achieved when 5min SiNx layer was used compared with 0.78 eV without any SiNx nanonetwork. Furthermore, the breakdown voltage improved from 76 V to 250V when SiNx nanonetwork was used in otherwise identical structures.

In-Situ Fluorescence Strain Sensing of the Stress in Interconnects

1994 ◽  
Vol 356 ◽  
Author(s):  
Q. Wen ◽  
Q. Ma ◽  
D. R. Clarke
Keyword(s):  
Laser Beam ◽  
Frequency Shift ◽  
Sapphire Substrate ◽  
Deposition Temperature ◽  
Spectroscopic Properties ◽  
Optical Microscope ◽  
Strain Sensing ◽  
Sapphire Substrates ◽  
Optical Fluorescence

AbstractAn optical fluorescence method is introduced for determining the localized stresses in passivated aluminum lines on sapphire substrates containing a thin epitaxial ruby film at the AI/AI2O3 interface. The method is based on the piezo-spectroscopic properties of the ruby film, which acts as an in situ sensor. By focusing a laser beam through the sapphire substrate and onto the bottom of an aluminum line, the fluorescence from the ruby sensor can be excited and collected through an optical microscope. The frequency shift of the fluorescence lines is proportional to the stress in the aluminum line. To illustrate our observations two sets of measurements are presented: the spatial variation perpendicular to an interconnect line; and the temperature dependence on heating upto the deposition temperature of the SiN used to passivate the interconnects.

Epitaxial lateral overgrowth of GaN on sapphire substrates using in-situ carbonized photoresist mask

2011 ◽  
Vol 326 (1) ◽  
pp. 200-204 ◽  
Author(s):  
Sang-il Kim ◽  
Bumjoon Kim ◽  
Samseok Jang ◽  
A-young Kim ◽  
Jihun Park ◽  
...  
Keyword(s):  
Epitaxial Lateral Overgrowth ◽  
Sapphire Substrates ◽  
Lateral Overgrowth ◽  
Photoresist Mask
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