Detailed description of the presently preferred embodiments

Abstract

The present invention is a nitride compound semiconductor laser, in which a cleaved end face is flat, and a breakdown of a laser end face induced during an operation can be suppressed, which consequently enables a life to be prolonged. In the nitride compound semiconductor laser, a stress concentration suppression layer is formed between an active layer and a cap layer.

1 - 24 . (canceled)  
     
     
         25 . A nitride semiconductor laser including a stress concentration suppressing layer between an active layer and a cap layer, the stress concentration suppressing layer relaxing a change in a band gap between the active layer and the cap layer, said laser further comprising: 
 an n-type cladding layer on a side opposite to the stress concentration suppressing layer of the active layer; and    a p-type cladding layer on a side opposite to the stress concentration suppression layer of the cap layer,    wherein,    a band gap of the active layer is smaller than band gaps of said n-type and p-type cladding layers,    a band gap of the cap layer is larger than the band gap of the p-type cladding layer,    an n-type optical guiding layer is further formed between the active layer and the n-type cladding layer, and comprises an n-type GaN containing Si as n-type impurities,    a p-type optical guiding layer is further formed between the p-type cladding layer and the cap layer, and comprises a p-type GaN containing Mg as p-type impurities, and    an Al composition ratio in the cap layer is composed of AlGaN to 0.15.