Semiconductor device and its manufacturing method
AssigneeFuji Electric Co., Ltd.
InventorYoshiaki Toyoda
Life of this patent
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Abstract
A semiconductor device includes: a substrate of a first conductivity type; a first diffusion layer of a second conductivity type provided in an upper part of the substrate; a conductive layer embedded in a trench provided in an upper part of the first diffusion layer via an insulating film, the conductive layer forming a capacitive element together with the first diffusion layer and the insulating film; and a second diffusion layer of the first conductivity type provided in an upper part of the first diffusion layer so as to be shallower than the trench and to constitute a resistive element, wherein at least a part of the trench and at least a part of the second diffusion layer are alternately arranged side by side in a plan view.
Claims18
A semiconductor device, comprising:
- a substrate of a first conductivity type;
- a first diffusion layer of a second conductivity type provided in an upper part of the substrate;
- a conductive layer embedded in a trench provided in an upper part of the first diffusion layer via an insulating film, the conductive layer forming a capacitive element together with the first diffusion layer and the insulating film;
- and
- a second diffusion layer of the first conductivity type provided in an upper part of the first diffusion layer so as to be shallower than the trench and to constitute a resistive element,
- wherein at least a part of the trench and at least a part of the second diffusion layer are alternately arranged side by side in a plan view.
A method for manufacturing a semiconductor device, comprising:
- forming in an upper part of a substrate of a first conductivity type a first diffusion layer of a second conductivity type;
- forming a second diffusion layer of the first conductivity type that constitutes a resistive element in an upper part of the first diffusion layer;
- forming a trench deeper than the second diffusion layer in an upper part of the first diffusion layer;
- and
- embedding a conductive layer film into the trench through an insulating film, thereby forming a capacitive element together with the first diffusion layer and the insulating film,
- wherein at least a part of the trench and at least a part of the second diffusion layer are alternately arranged side by side in a plan view.
Dependencies are inferred from the claim text.