Semiconductor device and production method thereof

A method for producing a semiconductor device comprising:

• a step of preparing a structure provided with a substrate, a planar semiconductor layer formed above the substrate and a columnar semiconductor layer formed on the planar semiconductor layer;
• a step of forming a first source or drain region in a lower part of the columnar semiconductor layer and in the planar semiconductor layer;
• a step of forming a gate insulating film around the columnar semiconductor layer;
• a step of forming a gate electrode on the gate insulating film so as to surround the columnar semiconductor layer;
• a second drain or source region formation step of forming a second drain or source region in an upper part of the columnar semiconductor layer;
• a contact stopper film formation step of forming a contact stopper film on a resultant structure of the second drain or source region formation step;
• a step of forming a contact interlayer film on the contact stopper film so as to embed a resultant structure of the contact stopper film formation step;
• and
• a contact layer formation step of forming a first contact layer on the second drain or source region,
• wherein the contact layer formation step comprises:
• a pattern formation step of forming a first pattern on the contact interlayer film, the first pattern corresponding to a region where the first contact layer is to be formed;
• a contact hole formation step of etching the contact interlayer film to the contact stopper film using the first pattern so as to form a first contact hole for the first contact layer;
• and
• a contact stopper film removal step of removing the contact stopper film remaining at a bottom of the first contact hole by etching, and a projection of a bottom surface of the first contact hole onto the substrate is within a circumference of a projected profile of the contact stopper film formed on a top surface and an upper sidewall of the columnar semiconductor layer onto the substrate.