Haruo Matsumaru

A new a-Si TFT with Al/sub 2/O/sub 3//SiN double-layered gate insulator for 10.4-inch diagonal multicolor display

A novel a-Si TFT (thin film transistor) with an Al gate electrode and an Al/sub 2/O/sub 3//SiN double-layered gate insulator has been developed and successfully applied to a 10.4-in diagonal multicolor display panel. Al is a low resistivity metal and it is also possible to form Al/sub 2/O/sub 3/ by anodic oxidation. These features contribute greatly to decreasing the number of defects in the panel and are indispensable for manufacturing a large-size display. The Al, which is used as a gate electrode, can also be used as a gate bus-line metal. As a result, the gate bus-line resistance of the panel can be reduced to about 2 k Omega , which is quite effective for improving the image quality of the panel.<<ETX>>

Phosphorus diffusion effect on off-current of a-Si thin film transistors

Abstract The off-current of a hydrogenated amorphous silicon thin film transistor is found to be affected by phosphorus diffusion from the n-layer to the i-layer during the n-layer deposition. The phosphorus diffusion coefficient is estimated to be 1.6×10−15cm2/sec at 380°C, and its activation energy is estimated to be 1.6eV. Removal of this phosphorus diffused region in the i-layer is indispensable for obtaining a low off-current.

Amorphous silicon thin film transistor with a buried double-gate structure

An amorphous silicon thin-film transistor (a-Si TFT) with a novel structure is described. A second gate electrode is introduced into a gate insulator of silicon nitride in addition to the conventional staggered a-Si TFT gate electrode. The performance of this TFT is characterized in terms of geometry and operating conditions. Equivalent electron mobility up to 1.8 cm/sup 2//(V-s) is achieved for optimized designs. It is also confirmed that the newly developed TFT preserves high reliability. Results of I-V measurements demonstrated that the on-current of a buried double-gate (BD) TFT reaches three times that of a conventional TFT. The V/sub t/ shift of the BD-TFT is about one-third that of the conventional TFT for the same gate electric field. The performance is suitable for large-area, high-resolution liquid-crystal displays.<<ETX>>

Optical Characteristics of Corning 7059 Glass Films Deposited by RF Sputtering

Corning 7059 glass films deposited by rf sputtering under certain conditions showed coloration phenomena. From thermodynamical calculations for oxides in 7059 glass, it was deduced that BaO became oxygen diffident to absorb visible light. This was supported by the experiments. Refractive indices of rf sputtered 7059 films were a few percents higher than that of 7059 bulk. The increase in refractive indices was explained by the change in the compositions, which were detected by electron microprobe analyzer. BaO and Al2O3 in the films were increased by 5–10%, while SiO2 was decreased by 5–10% and B2O3 remained practically unchanged.

Tri-Electrode Vidicon for Use in a Single Tube Color TV Camera

3電極方式単管カラーカメラ用ビジコンを, 主として微細加工技術を検討することにより開発した.このビジコンは, ストライプ状色フィルターとそれに重ね合わさり2層配線法により相互接続されたストライプ状信号電極から成り立っている.3色の信号電流を独立した電極から取り出すことができるため, カメラは小型化でき, 色再現性, 一様性, 光量範囲を3管式相当にすることができる.