Patent ID: 9514944
Filing Date: 2016-12-06
CPC Classification: G11C,H01L

Claim Text:
1. A method of producing an SGT-including semiconductor device, the method comprising: a semiconductor-pillar-forming step of forming a semiconductor pillar on a semiconductor substrate; a first-impurity-region-forming step of forming a first impurity region below the semiconductor pillar, the first impurity region containing a donor impurity or an acceptor impurity; a second-impurity-region-forming step of forming a second impurity region in the semiconductor pillar so that the second impurity region is distanced from and above the first impurity region, the second impurity region having the same conductivity type as the first impurity region; a first-gate-insulating-layer-forming step of forming a first gate insulating layer on an outer periphery of the semiconductor pillar and at least a portion of the semiconductor pillar located between the first impurity region and the second impurity region; a first-gate-conductor-layer-forming step of forming a first gate conductor layer on an outer periphery of the first gate insulating layer; a first-insulating-layer-forming step of forming a first insulating layer so that the first insulating layer covers the semiconductor pillar and the first gate conductor layer; a second-insulating-layer-forming step of forming a second insulating layer on the semiconductor substrate and on an outer periphery of the first insulating layer, the second insulating layer being shorter than the semiconductor pillar; a hydrogen-fluoride-ion-diffusion-layer-forming step of forming a hydrogen fluoride ion diffusion layer having a particular thickness on the second insulating layer and the first insulating layer; a hydrogen-fluoride-gas-supplying step of supplying hydrogen fluoride gas to the hydrogen fluoride ion diffusion layer such that the hydrogen fluoride ion diffusion layer generates hydrogen fluoride ions and the hydrogen fluoride ions diffuse therein; a first-insulating-layer-etching step of etching a part of the first insulating layer on the hydrogen fluoride ion diffusion layer by using the hydrogen fluoride ions generated in the hydrogen fluoride ion diffusion layer from the hydrogen fluoride gas supplied to the hydrogen fluoride ion diffusion layer; and a hydrogen-fluoride-ion-diffusion-layer-removing step of removing the hydrogen fluoride ion diffusion layer after the first-insulating-layer-etching step, wherein an SGT is constituted by the first impurity region and the second impurity region that respectively function as a source and a drain or vice versa, the at least a portion of the semiconductor pillar located between the first impurity region and the second impurity region that functions as a channel between the drain and the source, the first gate insulating layer, and the first gate conductor layer.