transmitter module to which the semiconductor laser device is applied referring to fig4 in a semiconductor laser device 100 an electrode layer 20 covers the entire surface of a stripe 60 at its output end electrode layer terminals 20 b are formed at both side positions apart from a mesa 50 having a width of about 1 u03bcm by several to ten u03bcm by ion milling however the metalized layer of the electrode end 20 b is formed of two layers of ti pt also an au layer of the electrode layer 20 extends up to the au electrode layer end 20 a inside of the electrode end 20 b by 1 to 3 u03bcm the reason that the above configuration is applied is because a stress of ti pt and au which constitute the electrode layer 20 is not concentrated on the electrode layer end 20 b and the ti pt layer functions as a stress relaxation layer in the au electrode layer end 20 a that is largest in the layer thickness and large in the stress referring to fig5 a to 5e the fabricating process of the au electrode layer end 20 a in fig4 will be described fig5 a is a cross sectional view showing the main portion of the fabricating process after ti pt au has been deposited on the substrate fig5 b is a cross sectional view showing the main portion.