LED with small mesa width

A method for manufacturing a light emitting device comprising:

• providing a substrate, the substrate having a substrate area comprising a substrate length and a substrate width;
• forming a first active layer on the substrate, at least a first portion of the first active layer comprising a first electrical polarity;
• forming a light emitting region on the first active layer, the light emitting region being configured to emit light with a target wavelength between 200 nm and 300 nm;
• forming a second active layer on the light emitting region, at least a first portion of the second active layer comprising a second electrical polarity;
• forming a first electrical contact layer on the second active layer, wherein the first electrical contact layer comprises a first optical reflector;
• removing a portion of the first electrical contact layer, a third portion of the second active layer, a portion of the light emitting region, and a third portion of the first active layer to form a plurality of mesas, wherein each mesa of the plurality of mesas comprises:
• a mesa area comprising a mesa length and a mesa width, the mesa area being smaller than the substrate area, and the mesa width being smaller than twice a current spreading length of the light emitting device;
• a second portion of the first active layer having an area that is equal to the mesa area;
• a second portion of the light emitting region having an area that is equal to the mesa area;
• a second portion of the second active layer having an area that is equal to the mesa area;
• a second portion of the first electrical contact layer having an area that is equal to the mesa area;
• and
• a mesa top surface and mesa sidewall surfaces;
• forming a second electrical contact layer on an exposed portion of the first active layer;
• forming a passivation layer, after forming the second electrical contact layer, wherein the passivation layer is:
• on the first electrical contact layer;
• on the second electrical contact layer;
• on a remaining exposed portion of the first active layer;
• and on the mesa sidewall surfaces;
• removing first portions of the passivation layer to expose the first electrical contact layer;
• removing second portions of the passivation layer to expose the second electrical contact layer;
• forming a first terminal contact layer on the first electrical contact layer;
• and
• forming a second terminal contact layer on the second electrical contact layer.