Semiconductor device including a strain relaxation film
AssigneeRenesas Electronics Corporation
InventorsToshiyuki Takewaki, Hironobu Miyamoto
Life of this patent
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Abstract
The reliability of a power MISFET made of a nitride semiconductor material is improved. A strain relaxation film is disposed between a polyimide film and a gate electrode, to suppress a stress exerted on an electron supply layer and a channel layer from the polyimide film, and suppress a stress strain generated in the electron supply layer and the channel layer. As a result, a change in channel electron concentration in the channel layer is suppressed to prevent a threshold voltage or an on-resistance of the power MISFET from fluctuating.
Claims23
A semiconductor device, comprising:
- a nitride semiconductor layer;
- a gate electrode that is formed over the nitride semiconductor layer of an active region through a first insulating film, and extends in a first direction;
- a second insulating film that is formed to cover the gate electrode;
- a first contact hole that is spaced apart from the gate electrode on one side of the gate electrode, formed over the second insulating film, and extends in the first direction;
- a second contact hole that is spaced apart from the gate electrode on the other side of the gate electrode, formed over the second insulating film, and extends in the first direction;
- a source electrode that is formed within the first contact hole, and electrically connected to the nitride semiconductor layer;
- a drain electrode that is formed within the second contact hole, and electrically connected to the nitride semiconductor layer;
- a strain relaxation film that is formed over the second insulating film above the gate electrode;
- a third insulating film that is formed to cover the source electrode, the drain electrode, and the strain relaxation film;
- and
- a resin film that is formed over the third insulating film,
- wherein the gate electrode includes a first outermost sidewall and a second outermost sidewall which is opposite the first outermost sidewall, and the strain relaxation film is formed between the resin film and the first and second outermost sidewalls.
A semiconductor device, comprising:
- a nitride semiconductor layer;
- a gate pad that is formed over the nitride semiconductor layer through a first insulating film;
- a first gate bus electrode that is protruded from the gate pad in a first direction;
- a plurality of second gate bus electrodes that is protruded from the first gate bus electrode in a second direction orthogonal to the first direction;
- a second insulating film that is formed to cover the gate pad, the first gate bus electrode, and the plurality of second gate bus electrodes;
- a source pad that is formed over the second insulating film;
- a plurality of source bus electrodes that is protruded from the source pad in the second direction;
- a drain pad that is formed over the second insulating film, and spaced apart from the source pad so as to face the source pad in the second direction;
- a plurality of drain bus electrodes that is protruded from the drain pad in a direction opposite to the second direction;
- a third insulating film that is formed to cover the plurality of source bus electrodes and the plurality of drain bus electrodes;
- and
- a resin film that is formed over the third insulating film,
- wherein the respective source bus electrodes and the respective drain bus electrodes are alternately arranged along the first direction in a plan view, and
- wherein the respective source bus electrodes and the respective second gate bus electrodes are arranged to vertically overlap with each other through the second insulating film.
Dependencies are inferred from the claim text.