Growth and Measurement of Mg Doped AlGaN/GaN Superlattice with Low Resistiviy

2012 ◽  
Vol 549 ◽  
pp. 274-277
Author(s):  
Jun Feng Chen
Keyword(s):  
Al Content ◽  
Superlattice Structure ◽  
Annealing Conditions ◽  
Great Progress ◽  
Bulk Gan ◽  
P Type ◽  
Relationship Of ◽  
The Relationship ◽  
Mg Doped

Although the research of bulk GaN material has take great progress in recent years, while the high quality of p-type GaN material still is an obstacle to fabricate the HBT and LD devices. In this paper we growth a group of Mg doped AlGaN/GaN superlattices under variant conditions. The Hall, AFM, PL and HR-XRD measurement are taken to find the relationship of sample quality with the superlattice structure, growth and annealing conditions. The results show that the period length of about 9nm and Al content of 30% is the optimal structure; the best annealing temperature under tmosphere is about 540°C to 580°C. At last the p-type AlGaN/GaN superlattice with resistivity of 0.31Ω•cm is fabricated which can be utilize for the contact layers of blue LEDs.

Study on the P-Type Doping of AlGaN/GaN Superlattice for Blue LED

2011 ◽  
Vol 343-344 ◽  
pp. 97-100
Author(s):  
Jun Feng Chen
Keyword(s):  
Active Layer ◽  
Ohmic Contact ◽  
Annealing Temperature ◽  
Period Length ◽  
Blue Led ◽  
Al Content ◽  
Superlattice Structure ◽  
P Type ◽  
Relationship Of ◽  
The Relationship

We studied the relationship of the superlattice structure with the doping efficiency in detail by semi-classic calculation and follow experiment. The results show that period length of about 9nm and Al content of 30% is optimal. The Hall, AFM and PL measurement show that the best annealing temperature under atmosphere is about 540°C to 580°C. Finally we obtained the sample with resistivity of 0.31Ω·cm. It can be used for fabricating p type ohmic contact and active layer for blue LED.

scholarly journals High Conductivity of Mg-Doped Al0.3Ga0.7N with Al0.4Ga0.6N/AlN Superlattice Structure

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Zhiming Li ◽  
Jinping Li ◽  
Haiying Jiang ◽  
Yanbin Han ◽  
Yingjie Xia ◽  
...  
Keyword(s):  
Vapour Deposition ◽  
Chemical Vapour ◽  
Doping Profile ◽  
Morphological Properties ◽  
Organic Chemical ◽  
Superlattice Structure ◽  
Metal Organic ◽  
P Type ◽  
Mg Doped

The highly conductance of Mg-doped Al0.3Ga0.7N layer using low-pressure metal organic chemical vapour deposition (MOCVD) on Al0.4Ga0.6N/AlN superlattice structure was reported. The rapid thermal annealing (RTA) has been employed for the effective activation and generation of holes, and a minimum p-type resistivity of 3 Ω·cm for p-type Al0.3Ga0.7N was achieved. The RTA annealing impacted on electrical, doping profile and morphological properties of Mg-doped Al0.3Ga0.7N with Al0.4Ga0.6N/AlN superlattice structure have been also discussed. The quality of Mg-doped Al0.3Ga0.7N with Al0.4Ga0.6N/AlN superlattice structure degraded after annealing from HRXRD. At appropriate annealing temperature and time, surface morphology of Mg-doped Al0.3Ga0.7N can be improved. A step-like distribution of [Mg] and [H] in p-type Al0.3Ga0.7N was observed, and thermal diffusion direction of [Mg] and [H] was also discussed.

Using the alveograph in developing requirements for the quality of flour for wafer sheet production

2020 ◽  
Vol 29 (12) ◽  
pp. 52-58
Author(s):  
E.P. Meleshkina ◽  
◽  
S.N. Kolomiets ◽  
A.S. Cheskidova ◽  
◽  
...  
Keyword(s):  
Rheological Properties ◽  
Quality Indicators ◽  
Wheat Flour ◽  
Mathematical Statistics ◽  
Intended Purpose ◽  
The Future ◽  
Relationship Of ◽  
The Relationship

Objectively and reliably determined indicators of rheological properties of the dough were identified using the alveograph device to create a system of classifications of wheat and flour from it for the intended purpose in the future. The analysis of the relationship of standardized quality indicators, as well as newly developed indicators for identifying them, differentiating the quality of wheat flour for the intended purpose, i.e. for finished products. To do this, we use mathematical statistics methods.

Management of Economics and State "Bottom"

2020 ◽  
Vol 17 (6) ◽  
pp. 76-91
Author(s):  
E. D. Solozhentsev
Keyword(s):  
Quality Of Life ◽  
Artificial Intelligence ◽  
Probabilistic Models ◽  
Human Life ◽  
Special Software ◽  
Human Quality ◽  
Relationship Of ◽  
The Relationship

The scientific problem of economics “Managing the quality of human life” is formulated on the basis of artificial intelligence, algebra of logic and logical-probabilistic calculus. Managing the quality of human life is represented by managing the processes of his treatment, training and decision making. Events in these processes and the corresponding logical variables relate to the behavior of a person, other persons and infrastructure. The processes of the quality of human life are modeled, analyzed and managed with the participation of the person himself. Scenarios and structural, logical and probabilistic models of managing the quality of human life are given. Special software for quality management is described. The relationship of human quality of life and the digital economy is examined. We consider the role of public opinion in the management of the “bottom” based on the synthesis of many studies on the management of the economics and the state. The bottom management is also feedback from the top management.

DIAGNOSING QUALITY OF FRICTION SYSTEMS OF MECHANISMS OF DEVICES

2019 ◽  
Vol 1 (7) ◽  
pp. 10-13
Author(s):  
D. Yu. Ershov ◽  
I. N. Lukyanenko ◽  
E. E. Aman
Keyword(s):  
Surface Defects ◽  
Diagnostic Methods ◽  
Design Parameters ◽  
Diagnostic Model ◽  
Mechanical Assemblies ◽  
Local Defects ◽  
Relationship Of ◽  
The Relationship ◽  
Production And Operation

The article shows the need to develop diagnostic methods for monitoring the quality of lubrication systems, which makes it possible to study the dynamic processes of contacting elements of the friction systems of instrument mechanisms, taking into account roughness parameters, the presence of local surface defects of elements and the bearing capacity of a lubricant. In the present article, a modern diagnostic model has been developed to control the quality of the processes of production and operation of friction systems of instrument assemblies. With the help of the developed model, it becomes possible to establish the relationship of diagnostic and design parameters of the mechanical system, as well as the appearance of possible local defects and lubricant state, which characterize the quality of friction systems used in many mechanical assemblies of the mechanisms of devices. The research results are shown in the form of nomograms to assess the defects of the elements of friction mechanisms of the mechanisms of the devices.

scholarly journals Study on the relationship of depression, anxiety, lifestyle and eating habits with the severity of reflux esophagitis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Rongxin Wang ◽  
Jing Wang ◽  
Shuiqing Hu
Keyword(s):  
Quality Of Life ◽  
Logistic Regression ◽  
Regression Analysis ◽  
Logistic Regression Analysis ◽  
Reflux Esophagitis ◽  
Eating Habits ◽  
Positive Correlation ◽  
Relationship Of ◽  
The Relationship

Abstract Background The etiology of reflux esophagitis (RE) is multi-factorial. This study analyzed the relationship of depression, anxiety, lifestyle and eating habits with RE and its severity and further explored the impact of anxiety and depression on patients’ symptoms and quality of life. Methods From September 2016 to February 2018, a total of 689 subjects at Xuanwu Hospital Capital Medical University participated in this survey. They were divided into the RE group (patients diagnosed with RE on gastroscopy, n = 361) and the control group (healthy individuals without heartburn, regurgitation and other gastrointestinal symptoms, n = 328). The survey included general demographic information, lifestyle habits, eating habits, comorbidities, current medications, the gastroesophageal reflux disease (GERD) questionnaire (GerdQ), the Patient Health Questionnaire-9 depression scale and the General Anxiety Disorder-7 anxiety scale. Results The mean age and sex ratio of the two groups were similar. Multivariate logistic regression analysis identified the following factors as related to the onset of RE (p < 0.05): low education level; drinking strong tea; preferences for sweets, noodles and acidic foods; sleeping on a low pillow; overeating; a short interval between dinner and sleep; anxiety; depression; constipation; history of hypertension; and use of oral calcium channel blockers. Ordinal logistic regression analysis revealed a positive correlation between sleeping on a low pillow and RE severity (p = 0.025). Depression had a positive correlation with the severity of symptoms (rs = 0.375, p < 0.001) and patients’ quality of life (rs = 0.306, p < 0.001), whereas anxiety showed no such association. Conclusions Many lifestyle factors and eating habits were correlated with the onset of RE. Notably, sleeping on a low pillow was positively correlated with RE severity, and depression was positively related to the severity of symptoms and patients’ quality of life.

Self-Perception of Voice and Swallowing Handicap in Parkinson’s Disease

2021 ◽  
pp. 1-8
Author(s):  
Alice K. Silbergleit ◽  
Lonni Schultz ◽  
Kendra Hamilton ◽  
Peter A. LeWitt ◽  
Christos Sidiropoulos
Keyword(s):  
Quality Of Life ◽  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Disease Duration ◽  
Self Perception ◽  
Functional Aspects ◽  
Dysphagia Handicap Index ◽  
Relationship Of ◽  
The Relationship

Background: Hypokinetic dysarthria and dysphagia are known features of Parkinson’s disease; however, self-perception of their handicapping effects on emotional, physical, and functional aspects of quality of life over disease duration is less understood. Objective: 1) Based upon patient self-perception, to determine the relationship of the handicapping effects of dysphagia and dysphonia with time since diagnosis in individuals with Parkinson’s disease; 2)To determine if there is a relationship between voice and swallowing handicap throughout the course of Parkinson’s disease. Method: 277 subjects completed the Dysphagia Handicap Index and the Voice Handicap Index. Subjects were divided into three groups based on disease duration: 0–4 years, 5–9 years, and 10 + years. Results: Subjects in the longer duration group identified significantly greater perceptions of voice and swallowing handicap compared to the shorter duration groups. There was a significant positive correlation between the DHI and VHI. Conclusion: Self-perception of swallowing and voice handicap in Parkinson’s disease are associated with later stages of disease and progress in a linear fashion. Self-perception of voice and swallowing handicap parallel each other throughout disease progression in Parkinson’s disease. Individuals may be able to compensate for changes in voice and swallowing early while sensory perceptual feedback is intact. Results support early targeted questioning of patient self-perception of voice and swallowing handicap as identification of one problem indicates awareness of the other, thus creating an opportunity for early treatment and maintenance of swallowing and communication quality of life for as long as possible.

scholarly journals Relationship of patient shame to working alliance and satisfaction: a preliminary investigation

2019 ◽  
Vol 14 (4) ◽  
pp. 251-263
Author(s):  
Daniel J. Carabellese ◽  
Michael J. Proeve ◽  
Rachel M. Roberts
Keyword(s):  
Patient Satisfaction ◽  
Working Alliance ◽  
Preliminary Investigation ◽  
Community Members ◽  
Content Type ◽  
Mediation Analyses ◽  
External Shame ◽  
Relationship Of ◽  
The Relationship

Purpose The purpose of this paper is to explore the relationship of two distinct variants of dispositional shame (internal and external shame) with collaborative, purpose-driven aspects of the patient–provider relationship (working alliance) and patient satisfaction. The aim of this research was to conduct a preliminary investigation into the relevance of dispositional shame in a general healthcare population. Design/methodology/approach In total, 127 community members (mean age 25.9 years) who reported that they had regularly seen a GP over the past year were recruited at an Australian university. Participants were asked to reflect on their relationship with their GP, and completed instruments assessing various domains of shame, as well as working alliance and patient satisfaction. Findings Non-parametric correlations were examined to determine the direction and strength of relationships, as well as conducting mediation analyses where applicable. Small, negative correlations were evident between external shame and working alliance. Both external and internal shame measures were also negatively correlated with patient satisfaction. Finally, the relationship of external shame to patient satisfaction was partially mediated by working alliance. Practical implications Both the reported quality of patient–provider working alliance, and level of patient satisfaction are related to levels of dispositional shame in patients, and working alliance may act as a mediator for this relationship. Originality/value The findings from this preliminary study suggest that internal and external shame are important factors to consider in the provision of medical care to maximise the quality of patient experience and working alliance.

Sign in / Sign up

Export Citation Format

Share Document