Abstract A process of forming a three region dielectric film on silicon and a semiconductor device employing such a film are disclosed. Silicon is oxidized in an oxygen-containing ambient. The oxidation step forms a first region of silicon oxide. Once oxidation has begun, reactive sputtering of aluminum in an oxygen plasma is initiated. This forms a second region of said dielectric film which comprises a mixture of silicon and aluminum oxides. A third region comprising substantially aluminum oxide is formed by the continuing reactive sputtering step. A semiconductor device comprising said three region dielectric film interposed between an electrode and a semiconductor body has little or no shift in threshold voltage providing good stability and can be fabricated in substantially less time and/or at lower temperatures than prior art methods.
A process of forming a dielectric film on a silicon body comprising: (a) oxidizing the surface of the silicon body in an oxygen-containing plasma to form a first region of said film comprising silicon oxide; (b) sputtering aluminum in said plasma to form a second region comprising a mixture of silicon and aluminum oxides over said first region; and, (c) forming a third region of substantially aluminum oxide over said second region by reactive sputtering of aluminum in said plasma.
Claim 2
Dependent Claim
80 words
A process of forming a dielectric film on a silicon body comprising: (a) oxidizing the surface of the silicon body in an oxygen-containing plasma to form a first region of said film comprising silicon oxide; (b) sputtering aluminum in said plasma to form a second region comprising a mixture of silicon and aluminum oxides over said first region; and, (c) forming a third region of substantially aluminum oxide over said second region by reactive sputtering of aluminum in said plasma.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein the temperature of the ambient is maintained below about 300° C.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein step (a) is preceded by the formation of a thickness of silicon dioxide on the silicon by thermal oxidation.
Claim 5
Dependent Claim
22 words
The process of claim 1 wherein the plasma has an effective power density of between about 1 and 15 Watts/cm 2 .
Claim 6
Dependent Claim
14 words
The process of claim 1 wherein step (a) is carried out by thermal oxidation.
Claim 7
Dependent Claim
19 words
The process of claim 5 wherein the thermal oxidation is carried out at a temperature of about 600° C.