Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
83 words
A process for growing gate oxides of different thicknesses on a semiconductor layer which comprises: a) growing a semiconductor layer on a substrate; b) depositing an oxide layer upon the semiconductor layer; c) amorphizing a selected area of the semiconductor layer; d) removing the oxide layer to expose the semiconductor layer having both amorphized and non-amorphized regions; and, e) growing gate oxide on the amorphized and non-amorphized regions of the semiconductor layer to provide gate oxides of different thicknesses on the semiconductor layer.
Claim 2
Dependent Claim
23 words
The process of claim 1 wherein the semiconductor layer is provided with a plurality of device tubs prior to growing the oxide layer.
Claim 3
Dependent Claim
37 words
The process of claim 1 or claim 2 wherein the oxide layer is grown on the substrate by heating the substrate to a temperature in the range from about 600°C to about 1200°C and oxidizing the substrate.
Claim 4
Dependent Claim
25 words
The process of any of the preceding claims wherein the oxide layer possesses a thickness in the range from about 60 to about 500 Å.
Claim 5
Dependent Claim
63 words
The process of any of the preceding claims wherein the step of amorphizing a selected area of the semiconductor layer is carried out by depositing a masking layer on the oxide layer and patterning the masking layer to provide a window which exposes a selected area of the oxide layer and thereafter implanting ions in the semiconductor layer underlying the exposed oxide layer.
Claim 6
Dependent Claim
21 words
The process of claim 5 wherein the ions are selected from the group consisting of silicon, fluorine, arsenic and mixtures thereof.
Claim 7
Dependent Claim
32 words
The process of claim 5 or claim 6 wherein the ions are implanted at a dose in the range from about 1x10 12 to about 5x10 16 ions per cm 2 .
Claim 8
Dependent Claim
27 words
The process of any of claims 5 to 7 wherein the ions are implanted at an energy in the range from about 5 to about 500 keV.
Claim 9
Dependent Claim
18 words
The process of any of the preceding claims wherein the oxide layer is annealed prior to being removed.
Claim 10
Dependent Claim
34 words
The process of any of the preceding claims wherein the gate oxide grown on the amorphized regions of the semiconductor layer possesses a thickness in the range from about 40 to about 500 Å.
Claim 11
Dependent Claim
34 words
The process of any of the preceding claims wherein the gate oxide grown on the non-amorphized regions of the semiconductor layer possesses a thickness in the range from about 20 to about 400 Å.
Claim 12
Dependent Claim
20 words
The process of any of the preceding claims further comprising: (f) fabricating devices on the gate oxides of different thicknesses.
Claim 13
Dependent Claim
37 words
The process of claim 12 wherein at least one device operates at a voltage in the range from about 1.8 to about 3.3 V and at least one device operates at a voltage of about 5 V.