Light emitting diodes with lattice matching sidewall passivation layer and method of making thereof

A method of forming a light emitting diode, comprising:

• forming a first-conductivity-type compound semiconductor layer, an active layer stack configured to emit light at a peak wavelength, and a second-conductivity-type compound semiconductor layer over a substrate;
• forming a mesa structure by etching the first-conductivity-type compound
• semiconductor layer, the active layer stack and the second-conductivity-type compound semiconductor layer;
• and
• forming a passivation material layer in contact with at least a sidewall of the mesa structure, wherein the passivation material layer comprises a first crystal structure that matches a second crystal structure of the first-conductivity-type compound semiconductor layer and the second-conductivity-type compound semiconductor layer,
• wherein the first-conductivity-type compound semiconductor layer and the second-conductivity-type compound semiconductor layer comprise phosphorous, and
• wherein the passivation material layer comprises ZnS, GaAs or GaP.

A light emitting diode, comprising:

• a mesa structure comprising a first-conductivity-type compound semiconductor layer, an active layer stack configured to emit light at a peak wavelength, and a second-conductivity-type compound semiconductor layer;
• and
• a passivation material layer contacting at least a sidewall of the mesa structure, wherein the passivation material layer comprises a first crystal structure that matches a second crystal structure of the first-conductivity-type compound semiconductor layer and the second-conductivity-type compound semiconductor layer,
• wherein the passivation material layer comprises ZnS, GaAs or GaP.