Semiconductor light emitting device and method of manufacturing semiconductor light emitting device

A method of manufacturing a semiconductor light emitting device, comprising:

• forming, on a substrate, an n-type clad layer made of an n-type aluminum gallium nitride (AlGaN)-based semiconductor material containing silicon (Si) and having a molar fraction of aluminum nitride (AlN) of not lower than 20% and not higher than 80%;
• forming, on the n-type clad layer, a first intermediate layer made of an AlGaN-based semiconductor material that contains Si;
• forming, on the first intermediate layer, a second intermediate layer made of an AlGaN-based semiconductor material having an Si concentration higher than that of the first intermediate layer and having a molar fraction of aluminum nitride (AlN) lower than that of the first intermediate layer;
• forming, on the second intermediate layer, an active layer made of an AlGaN-based semiconductor material configure to emit deep ultraviolet light having a wavelength of 355 nm or shorter;
• forming a p-type semiconductor layer on the active layer;
• removing a portion of the p-type semiconductor layer, the active layer, the second intermediate layer, and the first intermediate layer to expose a partial region of the n-type clad layer;
• and
• forming an n-side electrode in the partial region on the n-type clad layer, wherein
• a substrate temperature in the forming of the first intermediate layer and the second intermediate layer is lower than a substrate temperature in the forming of the n-type clad layer.