Reflective ohmic contacts for silicon carbide including a layer consisting essentially of nickel, methods of fabricating same, and light emitting devices including the same

A contact for silicon carbide comprising:

• a first layer consisting essentially of nickel on the silicon carbide;
• a second layer comprising silver and/or aluminum on the first layer opposite the silicon carbide;
• a third layer comprising platinum on the second layer opposite the first layer;
• and
• a fourth layer comprising gold on the third layer opposite the second layer.

A light emitting device comprising:

• a silicon carbide substrate having first and second opposing faces;
• a light emitting region on the second face;
• an ohmic contact on the diode region opposite the second face;
• a layer consisting essentially of nickel on the first face, which is configured to provide an ohmic contact to the first face and to allow transmission therethrough of optical radiation that emerges from the first face;
• a reflector layer on the layer consisting essentially of nickel opposite the first face;
• a barrier layer on the reflector layer opposite the layer consisting essentially of nickel;
• and
• a bonding layer on the barrier layer opposite the reflector layer.

A light emitting device comprising:

• a silicon carbide substrate having first and second opposing faces;
• a light emitting region on the second face;
• an ohmic contact on the light emitting region opposite the second face;
• a first layer consisting essentially of nickel on the first face;
• a second layer comprising silver and/or aluminum on the first layer opposite the first face;
• a third layer comprising platinum on the second layer opposite the first layer;
• and
• a fourth layer comprising gold on the third layer opposite the second layer.

A method of fabricating a light emitting device comprising:

• depositing a first layer consisting essentially of nickel on a first face of a silicon carbide substrate that includes a light emitting region on a second face thereof;
• depositing a second layer comprising silver and/or aluminum on the first layer opposite the first face;
• depositing a third layer comprising platinum on the second layer opposite the first layer;
• depositing a fourth layer comprising gold on the third layer opposite the second layer;
• and
• bonding the fourth layer to an external element, wherein annealing is not performed during the depositing a first layer, between the depositing a first layer and the depositing a second layer, between the depositing a second layer and the depositing a third layer, between the depositing a third layer and the depositing a fourth layer, between the depositing a fourth layer and the bonding the fourth layer, and during the bonding the fourth layer.