Method of manufacturing a semiconductor device
AssigneeHitachi, Ltd.
InventorsHiroshi Shinriki, Masayuki Nakata, Kiichiro Mukai
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Abstract
When a MOSFET containing a tantalum pentoxide film as a gate insulating film is formed, ion implantation is applied such that the end of an insulating film containing a tantalum pentoxide film situates to the outside of a gate electrode to thereby form source and drain regions. This can effectively prevent troubles such as short-circuitting due to tantalum pentoxide film and a highly reliable MOSFET can be obtained without applying light oxidation.
Claims42
A method of manufacturing a semiconductor device comprising the following steps:
- (a) a step of forming a first insulating film on a main surface of a semiconductor substrate, the first insulating film being a laminate of a first layer of an oxide of material of the semiconductor substrate, and a second oxide layer, the second oxide layer being formed of an oxide selected from the group consisting of tantalum pentoxide, niobium oxide, yttrium oxide, hafnium oxide, zirconium oxide and titanium oxide, the first layer being formed by applying a heat treatment to the semiconductor substrate in a dry oxidizing atmosphere,
- (b) a step of laminating a conductive film of a material selected from the group consisting of tungsten and molybdenum on said first insulating film,
- (c) a step of removing an unnecessary portion of said conductive film thereby forming a gate electrode and exposing the surface of said first insulating film extending beyond edges of the gate electrode, and
- (d) while the first insulating film extends beyond the edges of the gate electrode, a step of implanting impurity ions into predetermined surface regions of said semiconductor substrate, thereby forming source and drain regions.
A manufacturing method as defined in claim 3, wherein the second insulating film has substantially the same shape and substantially the same size as those of the conductive film.
A manufacturing method as defined in claim 42, wherein said semiconductor substrate is of a first conductivity type, and the impurity ions are of a second conductivity type opposite to the first conductivity type.
A method of manufacturing a semiconductor device comprising the following steps:
- (a) a step of forming a first insulating film comprising a laminate, the laminate including a silicon oxide layer and an oxide layer formed of an oxide selected from the group consisting of tantalum pentoxide, niobium oxide, yttrium oxide, hafnium oxide, zirconium oxide and titanium oxide, on the main surface of a semiconductor substrate, the silicon oxide layer being formed by applying a heat treatment to the semiconductor substrate in a dry oxidizing atmosphere,
- (b) a step of laminating a conductive film of a material selected from the group consisting of tungsten and molybdenum on said first insulating film,
- (c) a step of removing an unnecessary portion of said conductive film thereby forming a gate electrode and exposing the surface of said first insulating film extending beyond edges of the gate electrode, and
- (d) while the first insulating film extends beyond the edges of the gate electrode, a step of implanting impurity ions into predetermined surface regions of said semiconductor substrate, thereby forming source and drain regions.
A manufacturing method as defined in claim 46, wherein said semiconductor substrate is of a first conductivity type, and the impurity ions are of a second conductivity type opposite to the first conductivity type.
Dependencies are inferred from the claim text.