Awatar Singh

Window size effect on lateral growth of nickel silicide

Window size effect on lateral growth of nickel silicide in contact windows cut into oxide grown on Si (100) is studied. The growth rate is found to be independent of window size and follows the diffusion‐limited process with activation energy of 1.5 eV. The Si erosions are observed to grow due to predominant Si diffusion for vacuum anneal above 600 °C. This phenomenon becomes greatly pronounced with fine windows of 2 μm in diameter. We attribute this to (i) an enhanced stress level in fine windows causing reduction in the growth temperature of epitaxial NiSi2 in the windows and (ii) difference in surface energies of epitaxial NiSi2 formed and the Si substrate resulting in the shrinkage of the epitaxial NiSi2 dimension in the window. No such behavior is observed under identical conditions when Si (111) is used. We believe this is due to the fact that the lateral growth of nickel silicide in this case is about a quarter of that for Ni‐Si (100) lateral samples. Finally the technological importance of this study is pointed out.

Film thickness and grain size diameter dependence on temperature coefficient of resistance of thin metal films

The combined effect of film thickness and grain size diameter on the temperature coefficient of resistance of a uniform continuous polycrystalline metal film of thickness greater than the intrinsic mean free path has been theoretically investigated. It has been found that the value of the temperature coefficient of resistance decreases with decrease in grain size. For very small grain size it is less than the bulk value and may be negative in some cases, whereas for very large grain size and film thickness it approaches the bulk value.

Technique for lifting off thick film print fired on alumina

Abstract A technique for lifting off thick film DP 9596 print fired on alumina substrate is reported. The positive photoresist is used as a relief mask. Various applications of the technique are also pointed out.

Discharge treated thin films

Abstract This letter reports the results of a preliminary study of discharge treated thin films of aluminium, nichrome, molybdenum and tantalum vacuum deposited on oxidised silicon wafers and 7059 corning glass substrates. The possible applications of discharge treatment are also pointed out.

Techniques of adjusting thin- and thick-film resistors in hybrid microelectronic circuits

Abstract Various techniques of adjusting thin- and thick-film resistors in hybrid microelectronic circuits are briefly described and their relative merits and shortcomings pointed out.

Reverse photolithographic technique for thick film circuits

Abstract This paper deals with the reverse photolithographic technique, applied for the first time for the processing of thick film components on alumina substrates. The SEM photographs of the delineated patterns have revealed excellent edge line definition which is always saw-tooth shaped in the conventional process. Various VLSI application potentials have also been pointed out.

Reverse photo-lithographic technique for S.A.W. devices

Abstract This paper deals with the reverse photolithographic technique for the fabrication of S.A.W. devices such as convolver and correlator etc. In this technique, T-shaped negative relief mask is first applied to the substrate and the film is deposited subsequently. As a result, the film contacts the substrate directly only in the areas left open by the relief mask. The relief mask is finally removed by a solvent which attacks only the mask but not the film material.

Thin-film deposition techniques and design of thin-film passive components

Abstract Cathode sputtering and vacuum evaporation considered to be the important methods of thin-film depositions are described and their advantages and short-comings pointed out. The state of the art in the design of thin-film passive components such as resistors, capacitors, inductors, interconnection and cross-over is also described.

Thick film polyester screen on glass as photomask

Abstract The use of thick film polyester screen on glass as a conformal photomask is reported. This has been successfully used for defining oxide windows measuring 40 × 40 μm with same separation and down to 3 μm required for the simulation of silicide contact formation in device structures. The various advantages of this type of so called photomask have also been pointed out.

Discharge treatment technique of breaking alternate fingers of an interdigital transducer

This note reports a new technique of breaking alternate fingers of an interdigital transducer that is made of just one metal. The technique is based on the discharge treatment of the film. Various advantages of the technique are also pointed out.