Method for producing pillar-shaped semiconductor device
AssigneeUnisantis Electronics Singapore Pte. Ltd.
InventorsFujio MASUOKA, Nozomu HARADA
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Abstract
Regions including SiO2 layers, Si3N4 layers, and SiO2 layers, and C layers and SiO2 layers, whose two ends in Y-Y′ direction are located on the SiO2 layers and two ends in X-X′ direction are coincident with the rectangular SiO2 layers, are formed on an i-layer. The i-layer is etched using the SiO2 layers as masks to form Si pillar bases, and the C layers and the SiO2 layers are removed. Thereafter, the SiO2 layers are formed into a circular shape by isotropic etching using the Si3N4 layers as masks, and Si pillars are formed on the Si pillar bases using the circular SiO2 layers as masks.
Claims13
A method for producing a pillar-shaped semiconductor device, the method comprising:
- a step of forming, on a semiconductor layer, a band-shaped first material layer that extends in a first direction in plan view;
- a step of forming, on the band-shaped first material layer, a band-shaped second material layer that extends in a second direction different from the first direction in plan view;
- a step of forming an overlapping-portion first material layer at a portion where the band-shaped first material layer overlaps the band-shaped second material layer in plan view by etching the band-shaped first material layer using the band-shaped second material layer as a mask;
- a step of forming, on the band-shaped second material layer, a third material layer whose one or both ends are located, in plan view, on two opposite overlapping-portion first material layers among a plurality of the overlapping-portion first material layers aligned in the second direction;
- a step of forming a fourth material layer by etching the band-shaped second material layer using the third material layer as a mask;
- a step of forming a first semiconductor pillar base by etching the semiconductor layer using the overlapping-portion first material layer and the fourth material layer as etching masks;
- a step of removing the fourth material layer;
- and
- a step of forming a semiconductor pillar by etching the first semiconductor pillar base using the overlapping-portion first material layer as an etching mask,
- wherein a first pillar-shaped semiconductor device including the semiconductor pillar as a channel is formed.
Dependencies are inferred from the claim text.