MOCVD Growth of GaN on bulk AlN Substrates

1997 ◽  
Vol 482 ◽  
Author(s):  
Hong-Qiang Lu ◽  
Ishwara B. Bhat ◽  
Byung-Chan Lee ◽  
Glen A. Slack ◽  
Leo J. Schowalter
Keyword(s):  
Low Temperature ◽  
Preparation Method ◽  
Surface Preparation ◽  
The Other ◽  
Substrate Orientation ◽  
Exciton Emission ◽  
Plane Orientation ◽  
Mocvd Growth ◽  
Polishing Damage

AbstractIn this paper, the growth of epitaxial GaN layers on c-plane and a-plane bulk AIN substrates by metalorganic vapor phase epitaxy is reported. The AlN boules were grown by the sublimationrecondensation technique. Single crystal GaN films grown on the c-plane orientation replicate the substrate orientation. However the surface of the epilayer had a high density of cross-hatch defect lines, presumably caused by mechanical polishing damage. The low temperature PL spectra of these films were dominated by exciton emission at 3.470 eV with a FWHM of 14 meV at 7 K. On the other hand, GaN grown on the a-plane orientation AlN was polycrystalline and the surface was rough with ridge-like facets. The PL from this film showed a dominate peak at 3.406 eV which may originate from defect-bound excitons. The quality of the GaN layers grown on these AIN bulk substrates appeared to be limited by the surface preparation method, which has not been optimized.

MOCVD Growth of GaN Films on Lattice-Matched Oxide Substrates

1996 ◽  
Vol 449 ◽  
Author(s):  
O. M. Kryliouk ◽  
T. W. Dann ◽  
T. J. Anderson ◽  
H. P. Maruska ◽  
L. D. Zhu ◽  
...  
Keyword(s):  
Structural Quality ◽  
Film Properties ◽  
Cross Sectional ◽  
Substrate Orientation ◽  
Mocvd Growth ◽  
Dislocation Densities ◽  
Oxide Substrates ◽  
Lattice Matched ◽  
Gan Film

ABSTRACTThe use of the nearly lattice-matched oxide substrates LiGaO2 and LiAlO2 has been explored for growth of GaN by MOCVD. As compared to the quality of films grown on sapphire, only growth on LiGaO2 yielded good quality films, and required use of nitrogen as the carrier gas. Furthermore, high structural quality films were grown on LiGaO2 at temperatures as low as 850°C. Dislocation densities estimated from cross-sectional TEM micrographs were found to be as low as 107 cm-2 . HRTEM studies revealed deformations at the surface of the LiGaO2 adjacent to deposited GaN films, indicating possible interracial reactions which may affect the film properties. The GaN film orientations corresponded directly to the substrate orientation, viz., ({0001}/{001} and {1102}/{101}).

Effect of surface preparation on the quality of components after low-temperature carbonitriding

1984 ◽  
Vol 26 (5) ◽  
pp. 354-356
Author(s):  
V. B. Fridman ◽  
T. V. Egorshina ◽  
T. I. Kirpicheva ◽  
E. E. Chesalova
Keyword(s):  
Low Temperature ◽  
Surface Preparation ◽  
Effect Of Surface

Effect of Different Temperatures on Storage Quality of Fresh-Cut Apples

2014 ◽  
Vol 941-944 ◽  
pp. 1188-1191
Author(s):  
Qi Li ◽  
Chuan Zhu Leng ◽  
Si Xin Wang ◽  
Xi Hong Li ◽  
Lan Chen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Storage Time ◽  
The Other ◽  
Storage Quality ◽  
Treatment Groups ◽  
Titratable Acid ◽  
Different Temperatures ◽  
Mda Content ◽  
Fresh Cut

Taking ‘Fuji’ fresh-cut apples as material, studied on the effect of different temperatures (-2 ̊C,0 ̊C,2 ̊C and 4 ̊C) on storage quality of fresh-cut apples during 25 days. The results indicated that low temperature can significantly keep the storage quality of fresh-cut apples and inhibit browning. Moreover, compared to the other treatment groups, treatment at 0 ̊C better maintained the firmness, color, as well as higher contents of titratable acid and lower MDA content, which showed 0 ̊C can extent storage time.

scholarly journals EFFECTS OF LOW-TEMPERATURE ON THE QUALITY OF TURNIP ROOTS

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1127f-1127 ◽  
Author(s):  
V.I. Shattuck ◽  
Y. Kakuda ◽  
B.J. Shelp ◽  
N. Kakuda
Keyword(s):  
Low Temperature ◽  
Low Temperatures ◽  
The Other ◽  
Sensory Characteristics ◽  
Glucosinolate Content ◽  
Other Hand ◽  
Sugar Levels

The influence of low-temperature on the starch, sugar and glucosinolate content was studied in the mature roots of field and greenhouse-grown turnip. A decrease in both starch and sugar levels was recorded in roots after storage at 0°C for 4 weeks. On the other hand, when plants were exposed to a series of cold treatments, the starch level remained constant but the level of sugars increased in roots. In our studies, turnip roots exhibited the capacity to synthesize and degrade specific glucosinolates at low temperatures. The implications of these findings on the sensory characteristics of the root will be discussed.

The Food Value, Quality and Grading of Meat with Special Reference to Beef

1945 ◽  
Vol 1945 (01) ◽  
pp. 41-56
Author(s):  
E. H. Callow
Keyword(s):  
Low Temperature ◽  
The Other ◽  
Research Station ◽  
Secondary Effects ◽  
Beef Industry ◽  
New Approach ◽  
University Of Cambridge ◽  
The One ◽  
Food Value

During the war an investigation has been carried out at the Low Temperature Research Station, Cambridge, on the food value of beef. The beef animals were specially selected by Dr. J. Hammond, F.R.S. (School of Agriculture, University of Cambridge), and by the Meat and Livestock Division of the Ministry of Food, as being representative of the beef industry as a whole. The work on steers and heifers has already been published (Callow 1944), and that on cows will follow shortly. When the data from these investigations came to be analysed, it was found that sex, age and breed have only secondary effects on the food value of beef. The important factor is the stage of growth of the animal. In the present paper it is proposed to use this new approach to the old problem of the relation between grading on the one hand, and the food value and quality of beef on the other.

Initial Stages of MOCVD Growth of Gallium Nitride Using a Multi-Step Growth Approach

1997 ◽  
Vol 468 ◽  
Author(s):  
J. T. Kobayashi ◽  
N. P. Kobayashi ◽  
P. D. Dapkus ◽  
X. Zhang ◽  
D. H. Rich
Keyword(s):  
Low Temperature ◽  
Buffer Layer ◽  
Chemical Vapor ◽  
Buffer Layers ◽  
Mocvd Growth ◽  
Initial Stage ◽  
Step Growth ◽  
Van Der Pauw ◽  
Growth Approach

ABSTRACTA multilayer buffer layer approach to GaN growth has been developed in which the thermal desorption and mass transport of low temperature buffer layer are minimized by deposition of successive layers at increased temperatures. High quality GaN with featureless surface morphology has been grown on (0001) sapphire substrate by metalorganic chemical vapor deposition using this multilayer buffer layer approach. The lateral growth and coalescence of truncated 3D islands (TTIs) nucleated on low temperature buffer layers at the initial stage of overlayer growth is affected by the thickness of the final buffer layer on which nucleation of TTIs takes place. The effect of the thickness of this buffer layer on the quality of GaN is studied by using scanning electron microscopy, van der Pauw geometry Hall measurements and cathodoluminescence and an optimum value of 400Å is obtained.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

PENERAPAN iLEARNING SURVEY (iSur) DALAM MENINGKATKAN KUALITAS SISTEM INFORMASI SELAMA PROSES PEMBELAJARAN DI PERGURUAN TINGGI RAHARJA

CCIT Journal ◽  
2014 ◽  
Vol 7 (3) ◽  
pp. 335-354
Author(s):  
Untung Rahardja ◽  
Muhamad Yusup ◽  
Ana Nurmaliana
Keyword(s):  
Higher Education ◽  
Student Satisfaction ◽  
Teaching And Learning ◽  
Online Survey ◽  
The Other ◽  
Learning Activities ◽  
Faculty Performance ◽  
Satisfaction Measurement ◽  
Valid Information

The accuracy and reliability is the quality of the information. The more accurate and reliable, the more information it’s good quality. Similarly, a survey, the better the survey, the more accurate the information provided. Implementation of student satisfaction measurement to the process of teaching and learning activities on the quality of the implementation of important lectures in order to get feedback on the assessed variables and for future repair. Likewise in Higher Education Prog has undertaken the process of measuring student satisfaction through a distributed questioner finally disemester each class lecture. However, the deployment process questioner is identified there are 7 (seven) problems. However, the problem can be resolved by the 3 (three) ways of solving problems one of which is a system of iLearning Survey (Isur), that is by providing an online survey to students that can be accessed anywhere and anytime. In the implementation shown a prototype of Isur itself. It can be concluded that the contribution Isur system can maximize the decision taken by the Higher Education Prog. By using this Isur system with questions and evaluation forms are submitted and given to the students and the other colleges. To assess the extent to which the campus has grown and how faculty performance in teaching students class, and can be used as a media Isur valid information for an assessment of activities throughout college.

PENGARUH KUALITAS PRODUK DAN RELIGIUSITAS TERHADAP KEPUTUSAN NASABAH PRODUK SIMPANAN PADA BSM CABANG PURWOKERTO

2017 ◽  
Vol 4 (1) ◽  
pp. 189-215
Author(s):  
Yoiz Shofwa Shafrani
Keyword(s):  
Regression Analysis ◽  
Product Quality ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Analytical Tool ◽  
The Other ◽  
Financial Assets ◽  
Islamic Bank

Perkembangan dunia perbankan syariah tidak lepas dari peran para nasabah yang memberikan kepercayaan terhadap pihak perbankan untuk penyimpanan asset keuangannya. Faktanya banyak kelompok nasabah yang memutuskan untuk menjadi nasabah di perbankan syariah karena faktor religiusitasnya. Faktor lain yang dapat ikut mempengaruhi keputusan nasabah adalah kualitas produk. Di mana kualitas produk merupakan karakteristik yang melekat dari suatu produk. Kemungkinan yang terjadi bahwa kebanyakan nasabah pada perbankan syariah juga masih merupakan nasabah perbankan konvensional.Tujuan yang ingin dicapai dalam penelitian ini adalah untuk mengetahui pengaruh kualitas produk dan tingkat religiusitas nasabah terhadap keputusan nasabah untuk menyimpan dananya atau tidak di BSM Cabang Purwokerto. Alat analisis yang digunakan adalah analisis regresi linier berganda, dengan jumlah sampel 100 nasabah. Diperoleh hasil Y = 5,046 + 0,101X1 + 0,218X2. Berdasarkan uji F yang sudah dilakukan maka dapat diketahui bahwa variabel kualitas produk dan religiusitas secara bersama – sama berpengaruh terhadap keputusan nasabah untuk menyimpan dananya di BSM Cabang Purwokerto. Berdasarkan uji t yang sudah dilakukan dapat diketahui bahwa secara partial baik variabel kualitas produk maupun variabel religiusitas berpengaruh terhadap keputusan nasabah untuk menyimpan dananya di BSM Cabang Purwokerto. The progress of the Islamic bank cannot be separated from the role of its customers who give trust to the bank to deposit their financial assets. It is a fact many groups of customers decide to be the customers of the Islamic bank because of their religiosity. The other influences factor of a customer’s decision is the quality of the product. The aim of this research was to determine the effect of product quality and level of customers’ religiosity towards customers’ decision whether to keep their funds in Syariah Mandiri Bank, Branch of Purwokerto, or not. The analytical tool used was multiple linear regression analysis, with a sample of 100 customers. The results indicate Y = 5,046 + 0,101X1 + 0,218X2. Based on F, it can be seen that both variables of product quality and religiosity simultanously affect the customers’ decision to keep theirfunds in BSM Branch of Purwokerto. Based on t test, it can be seen that independently, either variable of product quality or variables of religiosityinfluences the customers’ decision to keep their funds in BSM Branch of Purwokerto.

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