SOI structure semiconductor device and a fabrication method thereof

A SOI structure semiconductor device comprising:

• a silicon substrate;
• an insulating oxide layer formed on said silicon substrate;
• an insulating nitride layer formed on said insulating oxide layer;
• a SOI layer formed on said insulating nitride layer;
• a LOCOS oxide layer formed on said insulating nitride layer and contacting with said SOI layer in order to insulate said SOI layer;
• a gate insulation layer formed on said SOI layer;
• and
• a gate electrode formed on said gate insulation layer.

A SOI structure semiconductor device comprising:

• a silicon substrate;
• an insulating nitride layer formed on said silicon substrate;
• a SOI layer formed on said insulating nitride layer;
• a LOCOS oxide layer formed on said insulating nitride layer and contacting with said SOI layer in order to insulate said SOI layer;
• a gate insulation layer formed on said SOI layer;
• and
• a gate electrode formed on said gate insulation layer.

A method of manufacturing a SOI structure semiconductor device comprising the steps of:

• providing a SOI substrate including an insulating oxide layer and a silicon layer formed on the insulating layer;
• forming a gate oxide layer on the silicon layer of the SOI substrate;
• forming a nitride layer on the gate oxide layer;
• selectively removing the nitride layer, gate oxide layer and a part of the silicon layer, removed thickness of which is more than ¾ of the silicon layer within a LOCOS oxide forming area;
• oxidizing the partly removed silicon layer within the LOCOS oxide forming area so that a LOCOS oxide layer is formed;
• and
• forming a gate electrode on the gate oxide layer.

A method of manufacturing a SOI structure semiconductor device comprising the steps of:

• providing a SOI substrate including an insulating oxide layer and a silicon layer formed on the insulating layer;
• forming a gate oxide layer on the silicon layer of the SOI substrate;
• forming a nitride layer on the gate oxide layer;
• obliquely removing the nitride layer, the gate oxide layer and a part of the silicon layer within a LOCOS oxide forming area so that the part of the silicon layer is removed widely than the nitride layer;
• oxidizing the partly removed silicon layer within the LOCOS oxide forming area so that a LOCOS oxide layer is formed;
• and
• forming a gate electrode on the gate oxide layer.

A method of manufacturing a SOI substrate comprising steps of:

• providing a silicon substrate having a surface thereof;
• introducing oxygen ions into the silicon substrate from the surface of the silicon substrate so that an oxygen containing layer is formed in the silicon substrate positioned at a first depth from the surface of the silicon substrate;
• introducing nitrogen ions into the silicon substrate from the surface of the silicon substrate so that a nitrogen containing layer is formed in the silicon substrate positioned at a second depth from the surface of the silicon substrate which is closer to the surface of the silicon substrate than the first depth;
• and
• subjecting the silicon substrate including the oxygen containing layer and the nitrogen containing layer to a heat treatment so that the oxygen containing layer and the nitrogen containing layer are transformed to an insulating oxide layer and an insulating nitride layer, respectively.

A method of manufacturing a SOI substrate comprising steps of:

• providing a silicon substrate having a surface thereof;
• introducing nitrogen ions into the silicon substrate from the surface of the silicon substrate so that an nitrogen containing layer is formed in the silicon substrate positioned at a first depth from the surface of the silicon substrate;
• and
• subjecting the silicon substrate including the nitrogen containing layer to a heat treatment so that the nitrogen containing layer is transformed to an insulating nitride layer.

A method of manufacturing a SOI structure semiconductor device comprising the steps of:

• preparing a silicon substrate having an element formation area and isolation area on a surface thereof;
• forming a mask layer on the element formation area of the silicon substrate, the mask layer inhibiting a passage of oxygen ions;
• introducing oxygen ions within the silicon substrate from the surface of the silicon substrate so that an oxygen containing layer is formed in the silicon substrate positioned at a first depth from the surface of the silicon substrate under the element formation area
• removing the mask layer and forming an anti-oxidation mask layer on the silicon substrate within the element formation area so that the surface of the silicon substrate within the isolation area is exposed;
• and
• subjecting the silicon substrate including the oxygen containing layer and exposed isolation area to a heat treatment so that the oxygen containing layer is transformed to an insulating oxide layer under the isolation area and the silicon substrate of the exposed portion is transformed to a LOCOS oxide layer and that the LOCOS oxide layer and the insulating oxide layer is contacting each other.

A method of manufacturing a SOI structure semiconductor device comprising the steps of:

• providing a SOI structure semiconductor device including a silicon substrate, an insulating oxide layer formed on said silicon substrate, a SOI layer formed on said insulating oxide layer, a LOCOS oxide layer formed on said insulating oxide layer and contacting with said SOI layer in order to insulate said SOI layer;
• introducing a first impurity into the SOI layer with a threshold value control implant so that a peak value of a profile of the first impurity is located at lower portion of the SOI layer;
• forming a gate insulating layer on the SOI layer;
• and
• forming a gate electrode on the gate oxide layer.