Nitride compound semiconductor element and method for manufacturing same
View Patent ↗The present invention is directed to a production method for a nitride compound semiconductor element including a substrate and a multilayer structure 40 supported by an upper face of the substrate. First, a wafer 1 to be split into individual substrates is provided. A plurality of semiconductor layers composing the multilayer structure 40 are grown on the wafer 1 . By cleaving the wafer 1 and the semiconductor layers, a cleavage plane in the multilayer structure 40 is formed. In the present invention, a plurality of voids are arranged at positions in the multilayer structure at which a cleavage plane is to be formed. Thus, cleavage can be performed with a good yield.
1. A production method for a nitride compound semiconductor element including a substrate having an upper face and a lower face and a multilayer structure supported by the upper face of the substrate, the production method comprising:
a step of providing a wafer to be split into the substrate;
a step of growing a plurality of semiconductor layers composing the multilayer structure on the wafer; and
a step of performing cleavage of the wafer and the multilayer structure to form a cleavage plane,
further comprising a step of arranging a plurality of voids at positions where the cleavage plane is to be formed, wherein at least one of the plurality of voids is shaped so as to have a longitudinal axis along a cleavage direction,
wherein a cross section of each void in a plane which is parallel to the wafer is sized and shaped so as to be accommodated within a rectangular region of 10 μm×10 μm.
2. The production method of claim 1 , wherein the step of arranging the plurality of voids comprises a step of pressing a tip of a needle piece against an upper face of the multilayer structure to form depressions on the multilayer structure, the depressions functioning as the voids.
3. The production method of claim 2 , wherein an angle formed between a direction which is perpendicular to the wafer and a pressing direction when the tip of the needle piece is abutted against the upper face of the multilayer structure is set to 5° or more.
4. The production method of claim 2 , wherein the nitride compound semiconductor element is a semiconductor laser having as a resonator end face a cleavage plane which is parallel to a plane containing the pressing direction.
5. The production method of claim 1 , wherein
the plurality of semiconductor layers have an active layer, and the plurality of voids are formed so as to be deeper than the position of the active layers.
6. The production method of claim 1 , wherein
an optical waveguide is formed in the multilayer structure, and a plurality of trenches are formed between the plurality of voids and the optical waveguide.