Electron-beam-induced current measurements in silicon-on-insulator films prepared by zone-melting recrystallization

Enhanced diffusion of arsenic along grain boundaries and subboundaries in zone-recrystallized silicon-on-insulator films has been measured by electron-beam-induced current analysis of lateral pn junctions fabricated in the films. A four-hour diffusion at 1100 °C resulted in protrusions of arsenic at the junction edges which measured approximately 3–5 µm along the grain boundaries and only 1–2 µm along the subboundaries. The results suggest that under more ordinary thermal processing conditions, field-effect transistors with channel lengths greater than about 1.5 µm can be randomly positioned with respect to the more numerous subboundaries, but grain boundaries should be avoided

Plasma Dynamics

Contains reports on twenty research projects split into two sections.National Science Foundation (Grant ENG75-06242-A01)U. S. Energy Research and Development Administration (Contract E(11-1)-2766)U. S. Energy Research and Development Administration (Contract E(11-1)-3070

Association of Tinnitus and Electromagnetic Hypersensitivity: Hints for a Shared Pathophysiology?

BACKGROUND: Tinnitus is a frequent condition with high morbidity and impairment in quality of life. The pathophysiology is still incompletely understood. Electromagnetic fields are discussed to be involved in the multi-factorial pathogenesis of tinnitus, but data proofing this relationship are very limited. Potential health hazards of electromagnetic fields (EMF) have been under discussion for long. Especially, individuals claiming themselves to be electromagnetic hypersensitive suffer from a variety of unspecific symptoms, which they attribute to EMF-exposure. The aim of the study was to elucidate the relationship between EMF-exposure, electromagnetic hypersensitivity and tinnitus using a case-control design. METHODOLOGY: Tinnitus occurrence and tinnitus severity were assessed by questionnaires in 89 electromagnetic hypersensitive patients and 107 controls matched for age-, gender, living surroundings and workplace. Using a logistic regression approach, potential risk factors for the development of tinnitus were evaluated. FINDINGS: Tinnitus was significantly more frequent in the electromagnetic hypersensitive group (50.72% vs. 17.5%) whereas tinnitus duration and severity did not differ between groups. Electromagnetic hypersensitivity and tinnitus were independent risk factors for sleep disturbances. However, measures of individual EMF-exposure like e.g. cell phone use did not show any association with tinnitus. CONCLUSIONS: Our data indicate that tinnitus is associated with subjective electromagnetic hypersensitivity. An individual vulnerability probably due to an over activated cortical distress network seems to be responsible for, both, electromagnetic hypersensitivity and tinnitus. Hence, therapeutic efforts should focus on treatment strategies (e.g. cognitive behavioral therapy) aiming at normalizing this dysfunctional distress network

Plasma Dynamics

Contains research objectives and summary of research on twenty-one projects split into three sections, with four sub-sections in the second section and reports on twelve research projects.National Science Foundation (Grant ENG75-06242)U.S. Energy Research and Development Administration (Contract E(11-1)-2766)U.S. Energy Research and Development Agency (Contract E(11-1)-3070)U.S. Energy Research and Development Administration (Contract E(11-1)-3070)Research Laboratory of Electronics, M.I.T. Industrial Fellowshi

Enhanced electron-beam-induced current contrast of grain boundaries in silicon-on-insulator films

The direct electron-beam-induced current (EBIC) observation of electrical properties of grain boundaries in silicon-on-insulator (SOI) structures has always been hampered by the insulated structure to be measured. In this communication a new structure is proposed with which EBIC images of grain boundaries in as-grown SOI layers can be obtained. Implantation of fluorine in the layer causes an enhanced contrast of these boundaries.