Semiconductor devices having low threading dislocations and improved light extraction and methods of making the same

A light emitting diode, comprising:

• a conductive substrate comprising a substantially randomly or irregularly roughened growth surface suitable for supporting the growth of an epitaxial region thereon, wherein the roughened growth surface of the conductive substrate has an average roughness Ra of at least about 1 nanometer (nm);
• a diode region comprising an epitaxial region on the growth surface of the conductive substrate;
• and
• a first ohmic layer on a surface of the conductive substrate opposite the diode region and a second ohmic contact on a surface of the diode region opposite the conductive substrate.

A method of fabricating a semiconductor device structure suitable for use in the fabrication of electronic devices such as light emitting diodes, comprising:

• treating a substrate growth surface suitable for supporting the growth of an epitaxial region thereon to substantially randomly or irregularly roughen the growth surface sufficient to provide a growth surface having an average roughness Ra of at least about 1 nanometer (nm);
• forming an epitaxial region on the roughened growth surface of the substrate;
• and
• providing first and second ohmic contacts on opposite sides of said semiconductor device, such that said semiconductor device is a vertical semiconductor device.

A semiconductor device structure suitable for use in the fabrication of electronic devices such as light emitting diodes, comprising:

• a substrate comprising a substantially randomly or irregularly roughened growth surface suitable for supporting the growth of an epitaxial region thereon, wherein the roughened growth surface of the substrate has an average roughness Ra of at least about 1 nanometer (nm);
• a conductive buffer layer on said substrate;
• and
• a diode region on said conductive region, said diode region comprising:
• an active region capable of emitting radiation;
• an n-type layer along a first surface of the active region;
• and
• a p-type layer on a second, opposing surface of the active region.