Patent ID: 7709280

Claim:
A method of manufacture of a high power semiconductor laser with reduced divergence of output radiation, comprising: providing a semiconductor substrate; forming a stack of layers supported by the semiconductor substrate, comprising an active layer for generating light, and an n-doped and a p-doped cladding layers, wherein: the active layer is disposed between the n-doped and the p-doped cladding layers, wherein the n-doped and the p-doped cladding layers have first and second refractive indices, respectively, and wherein the first refractive index is larger than the second refractive index; and wherein in operation, the stack of layers generates a lasing optical mode having a far field divergence and a peak point, wherein the stack of layers is asymmetric with respect to the active layer, so as to shift the majority of the lasing optical mode towards the n-doped cladding layer while keeping the peak point of the lasing optical mode inside the active layer; the n-doped cladding layer includes an area of a tail of the lasing optical mode, wherein said tail has an optical power density of less than 0.03% of the optical power density at the peak point of the lasing optical mode, and wherein said area of the tail is characterized by a thickness and a refractive index; and wherein the thickness of the area of the tail, or the refractive index of the area of the tail is adjusted so as to lessen the far field divergence of the lasing optical mode.