Light-emitting semiconductor device

A light-emitting semiconductor diode comprising:

• a first n-type compound semiconductor layer containing at least gallium and nitrogen and provided on a top surface of an insulating substrate;
• a second p-type compound semiconductor layer of a second conductivity type containing at least gallium and nitrogen and provided covering only a central portion of the first n-type compound semiconductor layer;
• a central electrode provided over and contacting a central part of the second p-type compound semiconductor layer;
• a peripheral electrode provided on a peripheral portion of the first n-type compound semiconductor layer, said peripheral electrode being separated from and surrounding or nearly surrounding the central second p-type compound semiconductor layer and the central electrode along with an exposed portion of the first n-type compound semiconductor layer without any overlap between the peripheral electrode and the central electrode as viewed from above;
• and
• wherein light is provided from an area between opposing portions of the central and peripheral electrodes.

A laser diode comprising:

• a first compound semiconductor cladding layer of a first conductivity type provided on top of a substrate;
• a compound semiconductor active light emitting layer provided over only a central part of said first compound semiconductor cladding layer;
• a second compound semiconductor cladding layer of a second conductivity type provided over the active layer;
• a central electrode provided on a central part of said second compound semiconductor cladding layer;
• and
• a peripheral electrode provided on a peripheral part of said first compound semiconductor cladding layer at least partly surrounding but not in contact with said centrally located active layer covered by said second compound semiconductor cladding layer and the central electrode without any overlap between the peripheral electrode and the central electrode as viewed from above;
• and
• wherein light is produced along side edge portions of the active layer.