SENSOR FOR MEASURING FILM PROPERTIES

摘要

A sensor has first and second electrodes (32A), (32B) spaced to define a gap (34) therebetween. The electrodes are formed on a substrate which can be covered with a film of material. The width of the gap (34) is different at different positions on the electrodes (32). This results in a sensing characteristic which can be made substantially linear, without sensitivity varying with film thickness, which arises from the use of a constant gap width. The sensor can be used to detect or measure film or liquid layer thickness, or solid material deposition.