Residual Stresses and Flaws of Ground Silicon Nitride.

Residual stress field of HIPed silicon nitride rolling elements

The residual stress field of HIPed Si3N4 rolling elements were studied. Two kinds of HIPed Si3N4 ball blanks self-finished at different nominal lapping loads ranging from 1.3kgf/ball to 10.87kgf/ball and four kinds of commercially finished 1⁄2′′ (12.7mm) HIPed Si3N4 balls before, during and after RCF tests were investigated. The experimental results showed that in the finishing process of HIPed...

Pattern Photoresist Silicon Silicon Nitride Silicon Photoresist Silicon Nitride Silicon Etch Nitride Remove Photoresist

In this proposal we seek to establish a porous silicon based etching process in the WTC microfabrication laboratory. The new process will allow us to etch high aspect ratio holes through a wafer. Holes like these are important for decreasing the dead volume of connections between micro and macro systems and for increasing the complexity of micro-fluidic systems. At the present time, the minimum...

Silicon Nitride and Silicon Carbide

Origin of the residual acceptor ground-state splitting in silicon.

The residual ground-state splitting of acceptors in high-quality silicon has been studied intensely by different experimental techniques for several decades. Recently, photoluminescence studies of isotopically pure silicon revealed the ground-state splitting to result from the random distribution of isotopes in natural silicon. Here we present a new model that explains these surprising experime...

MICROSTRUCTURAL STUDY OF SILICON NITRIDE WHISKERS PRODUCED BY NITRIDATION OF PLASMA-SPRAYED SILICON LAYERS

plasma-sprayed silicon layers have been used to produce silicon nitride layers with fibrous microstructure which optimizes fracture toughness and strength. SEM examination of the specimens shows that the surface is covered by fine needles and whiskers of Si3N4.In order to study the oxygen contamination effect as well as other contaminants introduced during spraying and nitridation processes, su...