Light-emitting device and light-emitting apparatus

A light-emitting device, comprising:

• an epitaxial structure having a first surface and a second surface opposite to said first surface, and including
• a first type semiconductor layered unit that includes a first type window layer and a first type ohmic contact layer disposed at one side of said first type window layer;
• an active layer;
• and
• a second type semiconductor layered unit;
• wherein
• said first type semiconductor layered unit, said active layer, said second type semiconductor layered unit are disposed in such order along a direction from said first surface to said second surface,
• said first type window layer is disposed between said first type ohmic contact layer and said active layer,
• said first type ohmic contact layer contains a material represented by Alx1Gay1InP, where 0≤x1≤1, 0≤y1≤1,
• said first type window layer contains a material represented by Alx2Gay2InP, where 0<x2≤1, 0≤y2≤1, and
• said first type ohmic contact layer has an Al content lower than an Al content of said first type window layer.