Method of fabricating nitride based semiconductor substrate and method of fabricating nitride based semiconductor device

A method of fabricating a nitride based semiconductor device, comprising the steps of:

• depositing a first nitride based semiconductor layer on a base;
• processing the first nitride based semiconductor layer to have ridge portions and recess portions;
• coating side surfaces of the ridge portions and bottom surfaces of the recess portions with an amorphous insulating film;
• growing a second nitride based semiconductor layer on a region of the first nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the first nitride based semiconductor layer serving as seed crystal;
• depositing a layer having an active layer structure with an active layer interposed between semiconductor layers of different conductivity types, on the second nitride based semiconductor layer;
• and
• separating the second nitride based semiconductor layer from the ridge portions by irradiating the region corresponding to the seed crystal with a laser beam.

A method of fabricating a nitride based semiconductor substrate, comprising the steps of:

• depositing a first nitride based semiconductor layer on a base;
• depositing a second nitride based semiconductor layer on the first nitride based semiconductor layer;
• processing the first and second nitride based semiconductor layers to have ridge portions and recess portions;
• coating side surfaces of the ridge portions and bottom surfaces of the recess portions with an amorphous insulating film;
• growing a third nitride based semiconductor layer on a region of the second nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the second nitride based semiconductor layer serving as seed crystal;
• and
• separating the third nitride based semiconductor layer from the ridge portions by irradiating the region corresponding to the seed crystal with a laser beam, wherein
• the second nitride based semiconductor layer has a bandgap smaller than a bandgap of the third nitride based semiconductor layer.

A method of fabricating a nitride based semiconductor device, comprising the steps of:

• depositing a first nitride based semiconductor layer on a base;
• processing the first nitride based semiconductor layer to have first ridge portions and first recess portions;
• coating side surfaces of the first ridge portions and bottom surfaces of the first recess portions with an amorphous insulating film;
• growing a second nitride based semiconductor layer on a region of the first nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the first nitride based semiconductor layer serving as first seed crystal;
• processing the second nitride based semiconductor layer to have second ridge portions and second recess portions;
• coating side surfaces of the second ridge portions and bottom surfaces of the second recess portions with an amorphous insulating film;
• growing a third nitride based semiconductor layer on a region of the second nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the second nitride based semiconductor layer serving as second seed crystal;
• depositing a layer having an active layer structure with an active layer interposed between semiconductor layers of different conductivity types, on the third nitride based semiconductor layer;
• and
• separating the second nitride based semiconductor layer from the first ridge portions by irradiating the region corresponding to the first seed crystal with a laser beam.

A method of fabricating a nitride based semiconductor device, comprising the steps of:

• depositing a first nitride based semiconductor layer on a base;
• depositing a second nitride based semiconductor layer on the first nitride based semiconductor layer;
• processing the first and second nitride based semiconductor layers to have ridge portions and recess portions;
• coating side surfaces of the ridge portions and bottom surfaces of the recess portions with an amorphous insulating film;
• growing a third nitride based semiconductor layer on a region of the second nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the second nitride based semiconductor layer serving as seed crystal;
• depositing a layer having an active layer structure with an active layer interposed between semiconductor layers of different conductivity types, on the third nitride based semiconductor layer;
• and
• separating the third nitride based semiconductor layer from the ridge portions by irradiating the region corresponding to the seed crystal with a laser beam, wherein
• the second nitride based semiconductor layer has a bandgap smaller than a bandgap of the third nitride based semiconductor layer.

A method of fabricating a nitride based semiconductor device, comprising the steps of:

• depositing a first nitride based semiconductor layer on a base;
• processing the first nitride based semiconductor layer to have ridge portions and recess portions;
• coating side surfaces of the ridge portions and bottom surfaces of the recess portions with an amorphous insulating film;
• growing a second nitride based semiconductor layer on a region of the first nitride based semiconductor layer other than a region thereof coated with the amorphous insulating film, the region of the first nitride based semiconductor layer serving as seed crystal;
• depositing a layer having an active layer structure with an active layer interposed between semiconductor layers of different conductivity types, on the second nitride based semiconductor layer;
• and
• separating the second nitride based semiconductor layer from the ridge portions by irradiating the region corresponding to the seed crystal with a laser beam.