Patent ID: 8563343

Claim:
A method of manufacturing a laser diode device, comprising: forming a semiconductor laser bar including a semiconductor substrate having opposed front and rear surfaces and including, sequentially stacked on the front surface, a lower cladding layer, an active layer, an upper cladding layer, and a contact layer, wherein said semiconductor laser bar includes first and second spaced apart edges; forming, in said semiconductor laser bar, separation trenches extending transverse to and entirely from said first edge to said second edge of said semiconductor laser bar, wherein each closest pair of said separation trenches defines a mesa stripe between the pair of said separation trenches, each of said separation trenches has first and second wider portions respectively located along the first and second edges of said semiconductor laser bar and a narrower portion extending between and connected to said first and second wider portions of said separation trench, and said narrower portion is narrower at said front surface of said semiconductor substrate, in a direction parallel to said first and second edges, than said wider portions at said front surface of said semiconductor substrate; scribing, in said semiconductor laser bar, grooves extending parallel to said separation trenches, wherein said grooves do not extend fully between said first and second edges of said semiconductor laser bar and terminate before reaching said first and second edges of said semiconductor laser bar; and propagating cracks from said grooves, splitting said semiconductor laser bar along said grooves and forming cleaved surfaces extending from said bottom surface of said semiconductor substrate of said semiconductor laser bar to said separation trenches.