doped regions 28s and 28d forming source and drain regions doping of semiconductor substrate 20 is preferably accomplished by ion implantation if semiconductor body 20 is doped with p type dopants then regions 28s and 28d are preferably doped with n type dopants dopant concentration and ion implant energy levels are chosen to provide a relatively heavy say n doping for the source and drain rgions subsequent doping operations may also optionally be carried out to produce lightly doped source and drain region extensions these are discussed below next second ion implantation mask layer 26a is deposited and planarized as shown in fig4 layer 26a preferably comprises a material other than silicon nitride and certainly a material different than that used in first ion implantation mask layer 24 in particular this material may comprise polycrystalline silicon metal or silicon oxide preferable metals include molybdenum and tungsten or silicides such as tungsten silicide molybdenum silicide or titanium silicide in particular if layer 26a comprises metal or metal silicide then this material may be patterned as illustrated in fig5 to form metal electrode contacts 26 for the source and drain regions next as illustrated in fig6 the rest of first ion implantation mask layer 24 is removed further as shown in fig7 oxide spacer material is deposited on the sidewalls of layer 26 this deposition is accomplished by low pressure chemical vapor deposition using silane and nitrous oxide it is noted that formation of oxide spacer material 32 is shown only as being present in the channel region of the fet device being formed one mechanism for accomplishing this object is delaying the patterning of layer 26a shown in fig4 in such a sequence spacer oxide material 32 is deposited only in the active area.