Semiconductor laser device fabricating method

#The present invention relates to a semiconductor laser device fabricating method capable of forming a plurality of semiconductor lasers on one semiconductor substrate.

#In recent years, optical disks have been popularized, and their recording formats have had many divergences. When optical disks of different standards are optically read, lasers of different standards are needed. For example, in order to read two types of optical discs of a CD (Compact Disc) and a DVD (Digital Versatile Disc), an infrared laser of an emission wavelength at and around 780 nm and a red laser of an emission wavelength at and around 650 nm are needed.

#In the above case, there is demanded the appearance of a semiconductor laser device capable of emitting laser beams of two wavelengths in one package for the size reduction and cost reduction of the pickup.

#The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

#FIGS. 1A through 1C are sectional views of a semiconductor laser device formed by the semiconductor laser device fabricating method of this invention in the fabricating processes of the device;

#FIGS. 2D through 2F are sectional views in the fabricating processes continued from FIG. 1C;

#This invention will be described in detail below on the basis of the embodiments shown in the drawings.

#(First Embodiment)

#FIGS. 1A through 1C and 2D through 2F show the cross sections of a semiconductor laser device in the fabricating processes, the device being formed by the semiconductor laser device fabricating method of this embodiment. First of all, as shown in FIG. 1A, an n-type GaAs buffer layer 22, an n-type AlGaAs clad layer 23, an AlGaAs guide layer 24, a multiple quantum well active layer 25, a p-type AlGaAs guide layer 26, a p-type AlGaAs clad layer 27 and a p-type GaAs contact layer 28 are successively formed on an n-type GaAs substrate 21 by MOCVD (Metal-Organic Chemical Vapor Deposition), forming an AlGaAs-based semiconductor laser 29 as one example of the first semiconductor laser layer. In the above case, the uppermost p-type GaAs contact layer 28 is doped with Zn so that the carrier density becomes 5×1018 cm−3.