Method for manufacturing semiconductor light emitting device and semiconductor light emitting device wafer

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

• forming a nitride semiconductor layer including a light emitting layer on a major surface of a first substrate, the major surface being provided with an unevenness having a depression and a protrusion;
• bonding the nitride semiconductor layer to a second substrate;
• and
• separating the first substrate from the nitride semiconductor layer by irradiating the nitride semiconductor layer with light via the first substrate,
• the forming the nitride semiconductor layer including leaving a cavity in a space inside the depression of the unevenness while forming a thin film on an inner wall surface of the depression of the unevenness, the thin film including a same material as at least a part of the nitride semiconductor layer, the nitride semiconductor layer including a first portion facing the depression and a second portion facing the protrusion, and
• the separating including causing the thin film to absorb at least a part of the light so that an intensity of the light applied to the first portion is made lower than an intensity of the light applied to the second portion;
• wherein
• the protrusion is continuous, and the depression is provided in a plurality, and
• an angle between a side surface of an upper portion of the depression and a first axis perpendicular to the major surface is smaller than an angle between a side surface of a lower portion of the depression and the first axis.