Ngwe Cheong

P-119: New Multi-Domain Vertical Alignment LCD with High Contrast Ratio and Symmetrical Wide Viewing Angle Performance and Simplest Fabrication Design and Process

We invented and successfully fabricated a new multi-domain vertical alignment (MVA) LCD with high contrast ratio and wide symmetrical viewing-angle performance. The LCD has a simple fabrication process without rubbing, with no surface protrusion, and no ITO slit geometry. The new MVA LCD makes use of the intrinsic fringe field in each pixel to control the LC alignment, and manifesting 2 domains under column inversion and row inversion, and 4 domains under pixel inversion operation. The viewing angle can be enlarged by the use of optical compensation films, and transmission can be enlarged by improved LC material, drive voltage, pixel design and circular polarizers.

A simple electrical method to determine the Si and oxide thicknesses in SOI materials

It is shown that the thickness of the silicon and oxide layers of a silicon-on-insulator (SOI) structure can be determined from high-frequency capacitance-voltage measurements. The test device consists of a Schottky diode in series with a Si-oxide-Si capacitor. The Si film and the substrate are n-type. The operation of this device is explained for n-type Si with the help of the energy-band diagrams. It is demonstrated that this simple test device can be implemented as a process monitor for silicon thickness control.<<ETX>>

P-93: Process and Performance Improvements for a Simple Low-Cost Multi-Domain Vertical-Alignment LCD

Process and performance improvements have been made in Kopins simple, low-cost MVA liquid crystal display to bring the fabrication process closer to manufacturing. Key results include striation-free displays with spun-on polyimide alignment layers, elimination of boundary stick via pixel design, overall viewing angle improvement with an MVA-matched wide viewing polarizer, and transmission improvements with high delta n LC, cell gap, driving mode, LED and BEF backlight combination.

Recombination lifetime measurements in SOI materials using a depletion-mode MOSFET

The authors measured recombination lifetime in SOI by using a depletion-mode MOSFET. The drain-source current transient of depletion-mode MOSFETs when a reversed step bias is applied to the gate is studied at elevated temperatures. A theoretical analysis is performed by considering the different generation processes as functions of temperature. At high temperature, the minority carriers required for the inversion charge come mainly from the quasi-neutral region beneath the depletion region and from the nearby Si film-buried oxide interface through a generation-diffusion process; generation from the depletion region is neglected as well as the generation from the front gate interface. This analysis leads to a determination of a function containing the drain-source current varying linearly with time.<<ETX>>