Abstract: A solid state, touch sensitive position sensor, which sensor includes a conductive surface along the boundaries of which are disposed at least two sets of two elongated current distribution and collection means. The touch sensitive position sensor further includes resistance means operatively disposed so as to interconnect said current distribution and collection means with said conductive surface. The current distribution and collection means and resistance means are configured, so as to (1) provide a substantially linear electric field distribution of equipotential lines and (2) sequentially turn one set of said current distribution and collection means on while turning the other sets off. In an important embodiment, the conductive surface is formed immediately atop a copyboard and by utilizing erasable, felt tip markers having metallic inserts therein, visual images as well as electrical signals, indicative of X-Y coordinate location, may be simultaneously generated.

Abstract: Thin film semiconductor devices such as amorphous silicon alloy p-i-n diodes and the like which utilize mesa-like semiconductor structures having vertical sidewalls are formed by a process which eliminates overhangs and neutralizes contaminants on the sidewalls that can result in short circuits or degradation of device performance. Smooth vertical sidewalls free of overhangs and voids are created by: successively depositing the desired semiconductor layers on a substrate, then depositing and patterning a top metal contact mask on the semiconductor layers, followed by removing the unwanted portions of the semiconductor layers by reactive ion etching. The disclosed reactive ion etching provides controlled vertical etching with virtually no lateral etching, thereby providing smooth sidewalls.