ELECTRONIC PHYSIC ON A METAL-SEMICONDUCTOR INTERFACE

Metal-Si Schottky contacts have been made by using various metals in order to investigate thedependence of typical diode parameterssuch as the barrier height and the effective Richardson constanton a film thickness of the metal electrode. In any contact with a metal-electrode film below 400< ang > thickness,the Schottky barrier height evidently varies with the film thickness. the effective Richardsonconstant obtained by a photo电子仪器shows different valuesdepending upon the choice of metal, and also shows a metal-thickness dependence，contrary to the generally accepted theory for metal-semiconductor contacts. In particularthe effective Richardson constant in a sample made by rf sputtering shows a much largerfilm-thickness dependence than that in a sample by vacuum evaporation. Furthermore，for the purpose of investigating the cause of the change in the effective Richardson constant withthe metal-film thicknessa 1000-<Ang>-thick Pt film has been deposited by rf sputtering onto Si substrates which have beenheated to various temperatures between room temperature and 500 C. The barrier height and Theeffective Richardson constant for these Pt-Si contacts已在投资photoelectrically. Asa result,这之前就已经发现the dependences of the barrier height and the Richardson constant on thethickness of a sputtered plm quite agree with the dependences of those on the temperature of asi substrate。

Metal-Si Schottky contacts have been made by using various metals in order to investigate the dependence of typical diode parameters, such as the barrier height and the effective Richardson constant, on a film thickness of the metal electrode. In any contact with a metal-electrode film below 400 <Ang> thickness, the Schottky barrier height evidently varies with the film thickness. The effective Richardson constant obtained by a photoelectrical measurement shows different values, depending upon the choice of metal, and also shows a metal-thickness dependence, contrary to the generally accepted theory for metal-semiconductor contacts. In particular, the effective Richardson constant in a sample made by rf sputtering shows a much larger film-thickness dependence than that in a sample by vacuum evaporation. Furthermore, for the purpose of investigating the cause of the change in the effective Richardson constant with the metal-film thickness, a 1000-<Ang>-thick Pt film has been deposited by rf sputtering onto Si substrates which have been heated to various temperatures between room temperature and 500゜C. The barrier height and the effective Richardson constant for these Pt-Si contacts have been investigated photoelectrically. As a result, it has been found that the dependences of the barrier height and the Richardson constant on the thickness of a sputtered Pt film quite agree with the dependences of those on the temperature of a Si substrate.