Abstract of the Disclosure

A process for fabrication of semiconductor devices comprising the steps of depositing over the surface of a semiconductor wafer a first insulating layer containing impurities which are to be diffused into the wafer so as to form source and drain regions, depositing a second insulating and melt-flow layer which is softened or melted at low temperatures, opening contact windows, forming a third insulating layer which also contains impurities to be diffused into the wafer so as to form source drain regions, subjecting the wafer to a heat treatment so as to cause melt-flow and form source and drain regions by the diffusion and removing the third insulating layer. LSI circuits with a high source-drain breakdown voltage may be fabricated at high yields.

• schematic sectional views, on exaggerated scale, of the sequential steps of one embodiment of a process for fabrication of semiconductor devices in accordance with the present invention.

 Citations [54]:
  
3,825,442  07/1974  Moore
3,986,896  10/1976  Veno et al
3,986,903  10/1976  Watrous
4,079,504  03/1978  Kosa
4,102,733  07/1978  De La Moneda et al
4,114,256  09/1978  Thibault et al
4,151,631  05/1979  Klein