Optical characterisation of silicon nanocrystals embedded in SiO2/Si3N4 hybrid matrix for third generation photovoltaics

Silicon nanocrystals with an average size of approximately 4 nm dispersed in SiO2/Si3N4 hybrid matrix have been synthesised by magnetron sputtering followed by a high-temperature anneal. To gain understanding of the photon absorption and emission mechanisms of this material, several samples are characterised optically via spectroscopy and photoluminescence measurements. The values of optical band gap are extracted from interference-minimised absorption and luminescence spectra. Measurement results suggest that these nanocrystals exhibit transitions of both direct and indirect types. Possible mechanisms of absorption and emission as well as an estimation of exciton binding energy are also discussed

Integrated circuits on GaAs for the temperature range from room temperature up to 300°C

The purpose of this paper is to present a technology for GaAs integrated circuits which allows stable operation in the temperature range from 20°C to 300°C. We shall show by some examples that it is possible to fabricate MESFET-based integrated circuits with small temperature dependence up to 300°C. Long term thermal stress tests demonstrate the excellent reliability of the technology. However, the need for adequate design tools will be shown as well, as more complicated circuits have an unpredictable behaviour at very high temperatures

Microwave characterization and comparison of performance of GaAs based MESFETs, HEMTs and HBTs operating at high ambient temperatures

For the first time microwave measurements at ambient temperatures up to 300°C have been performed on especially fabricated GaAs MESFETs, GaAs/AlGaAs HEMTs and HBTs, de­signed for continous operation at ambient temperatures up to 300°C with high reliability. A technology is presented which allows the realization of MESFET, HEMT and HBT device per­formance at elevated ambient temperatures. Ohmic and Schottky contacts have been realized with Ni-Ge-Au-Ni~W5-Si2-Au and LaB6-Au, respectively. These results open new possibilities for various applications of such transistors

On PAR: A feasibility study of the Promoting Adult Resilience programme with mental health nurses

© 2018 Australian College of Mental Health Nurses Inc. Mental health settings are recognized as complex, unpredictable environments, and challenging interpersonal situations are common for nurses in acute adult mental health services. Occupational stressors include verbal aggression and physical assault and are correlated with poor physical and mental health outcomes for nurses. There is a clear need for proactive approaches that address the negative impacts of stressors on the mental health nursing workforce. Resilience interventions are a preventive approach to strengthening skills for addressing workplace stress, improving health and well-being, and preventing adverse outcomes associated with occupational stressors. The aim of this study was to evaluate the feasibility of a workplace resilience education programme for nurses in high-acuity adult mental health settings. The outcomes were measured using a single-group pretest post-test design with follow-up at 3 months postintervention. The feasibility and acceptability of the programme were identified with descriptors of mental health, well-being, resilience, facilitator fidelity checklists, and participant satisfaction questionnaires. The programme was found to be feasible for nurses working in high-acuity inpatient settings. There were significant changes to mental health, well-being, and workplace resilience. The programme was delivered with fidelity by facilitators and accepted with high levels of satisfaction by participants. The study findings indicated that nurses can benefit from resilience education that equips them with cognitive, emotion regulation, and relational skills, in conjunction with available external supports and resources, to address workplace challenges. There is a need for comprehensive organizational approaches that include individual, work unit, and organizational-level strategies to support staff well-being

CONDUCTION PROPERTIES AND THRESHOLD VOLTAGE INSTABILITY IN beta-Ga2O3 MOSFETs

In this paper we analyze the conduction properties, charge trapping and threshold voltage instability of normally-on beta-Ga2O3 lateral MOSFETs for high power applications by means of threshold voltage transients. We found that a positive bias applied to the gate induces a rightward shift in the threshold voltage, caused by the trapping of electrons at border traps close to the semiconductor-dielectric interface.The amount of trapped charge was investigated by an innovative fast-CV experimental setup and was found to follow a logarithmic kinetic in time, modeled by a generalization of the inhibition model that takes into account the effect of columbic repulsion in stress conditions.Then, we developed a model for the gate conduction based on temperature dependent I-G-V-G characteristics. We detected that the gate current characterized in temperature and bias conditions similar to the ones used for the stress is dominated by Poole-Frenkel conduction assisted by a deep level at E-C - 0.12 eV

School-based, two-arm, parallel, controlled trial of a culturally adapted resilience intervention to improve adolescent mental health in Vietnam: study protocol

INTRODUCTION: The Resourceful Adolescent Program (RAP) is an evidence-based resilience intervention for adolescents. Operating in a strength-focused paradigm, the programme uses an integration of cognitive behavioural therapy and interpersonal psychotherapy to improve coping skills and build resilience. This study aims to establish whether a culturally and linguistically adapted intervention informed by RAP principles is effective in increasing resilience, enhancing coping skills and preventing symptoms of depression and anxiety. METHODS AND ANALYSIS: We will translate, back-translate and culturally adapt the RAP for adolescents and training materials for facilitators, and the adapted intervention will be called Happy House. A two-arm parallel controlled trial will be conducted in eight high schools in the north of Vietnam. In each of the selected schools, all students from four randomly selected grade 10 classes (an estimation of about 1204 students) will be invited to participate. The control group will receive the usual curriculum. The intervention group will receive six weekly 90 min school-based group sessions of Happy House in addition to the usual curriculum. The primary outcome, depressive symptoms, will be measured using a locally validated version of the Centre for Epidemiologic Studies Depression Scale Revised. Secondary outcomes are mental well-being, coping self-efficacy, school connectedness, anger management and health risk behaviours. Data will be collected at recruitment, and at two weeks and six months post intervention. Mixed-effect logistic regression for the main outcome and mixed-effect linear and logistic regression models for the secondary outcomes will be conducted to estimate the effects of the intervention on the outcomes. ETHICS AND DISSEMINATION: This trial has been approved by Monash University Human Research Ethics Committee (No. 21455) and the Institutional Review Board of the Hanoi School of Public Health (488/2019/YTCC-HD3). Dissemination of findings will include peer-reviewed publications, international and national conferences, seminar and media presentations, national policy briefings in Vietnam, local language reports and lay language summaries for participants. TRIAL REGISTRATION NUMBERS: Registered with the Australian New Zealand Clinical Trials Registry, registration number: ACTRN12620000088943 (3/2/2020).WHO Universal Trial Number: U1111-1246-4079

Isolation properties and failure mechanisms of vertical Pt / n-GaN SBDs

This paper reports on the isolation properties and failure mechanism of n-type vertical Pt / n-GaN Schottky barrier diodes and the dependence on the drift layer doping concentration. The results indicate that (i) inde-pendently on doping density, the Schottky barrier height is lower than the theoretical expectation, and this limits the blocking properties of the junction; (ii) barrier lowering was associated to an injection mechanism that in-volves deep levels in the semiconductor layer, near the junction, favouring injection and tunneling of carriers. By performing a detailed analysis of the breakdown mechanism, we also demonstrated that (iii) the failure of the devices in reverse bias condition is related to a power-related mechanism associated to current flowing along the mesa edges. We thus conclude that (iv) a good edge termination and passivation of the surfaces is fundamental to exploit the full blocking capability of the semiconductor