Abstract: A phase-locked semiconductor laser device comprising a laminated structure in which a plurality of first semiconductor layers having the substantially same composition are stacked in a manner to be sandwiched between second semiconductor layers having a band gap wider, and a refractive index lower, than those of said first semiconductor layers; a third semiconductor layer which is disposed in contact with at least one of side faces of said laminated structure parallel to a traveling direction of a laser beam, which is not narrower in the band gap and not higher in the refractive index than said first semiconductor layers and which does not have the same conductivity type as, at least, that of said first semiconductor layers; means to inject current into an interface between said first semiconductor layers and said third semiconductor layer disposed on the side face of said laminated structure; and means to act as an optical resonator for the laser beam.

Abstract: The invention provides a solid state image pickup device having a plurality of photoelectric transducers and a vertical transfer CCD (charge coupled device) unit. A concentration of an impurity of a semiconductor substrate region surrounding each of the vertical transfer CCD in the vicinity of each of the photoelectric transducers is higher than that below each of the photoelectric transducers.

Abstract: In the fabrication of a solid-state image sensor of the type having a plurality of photoelectric transducer means on a semiconductor substrate of one conductivity, excessive charge drain regions each provided with a plurality of first electrodes and second electrodes which function as a gate for controlling the drain of excessive charge, impurities or dopants of the other conductivity are introduced immediately below each of the regions at which the first electrodes are to be formed; thereafter, the first and second electrodes are formed; and impurities or dopants which are same as the above-described impurities or dopants are introduced while using the first and second electrodes as a masking pattern, whereby the photoelectric transducer means and drain regions are formed.

Abstract: In a semiconductor laser device having at least a first semiconductor layer, second and third semiconductor layers which are formed in a manner to sandwich the first semiconductor layer and which have a wider band gap and a lower refractive index than those of the first semiconductor layer, an optical resonator and carrier injection means; a semiconductor laser device characterized in that at least said first semiconductor layer has an angle of inclination (.theta.) relative to an axis which is perpendicular to optically flat faces constituting said optical resonator. The inclination angle .theta. (rad) should most preferably lie in a range of: ##EQU1## where .theta..sub.z denotes a reflection angle, .theta..sub.c a critical angle, W 1/2 of a thickness of a waveguide, and l a cavity length. The laser device is effective for preventing laser facets from breaking down, and can produce high power.

Abstract: In a semiconductor laser device wherein a stripe-shaped impurity-diffused region is disposed in at least parts of semiconductor layers of from a surface semiconductor layer of a semiconductor layer assembly constituting the semiconductor laser device to a second semiconductor layer lying in contact with a first semiconductor layer having an active region, the impurity-diffused region having the same conductivity type as that of the second semiconductor layer and extending at least from the surface semiconductor layer to a depth vicinal to the first semiconductor layer, the impurity region serving as a current path; a semiconductor laser device characterized in that a third semiconductor layer in which the diffusion rate of an impurity for use in the formation of the impurity-diffused region is lower than in the second semiconductor layer is disposed between the surface semiconductor layer and the second semiconductor layer.

Abstract: In certain applications, it is desirable to have a semiconductor laser device having shorter wave lengths of oscillation than are possible with conventional semiconductor lasers. To accomplish this, a semiconductor laser device is formed having a double-hetero structure, which comprises a semiconductor substrate composed of a GaAsP crystal, a first cladding layer formed on the substrate and composed of a GaAlAsP crystal of one conducting type, an active layer formed on the first cladding layer and composed of GaInAsP crystal, and a second cladding layer formed on the active layer and composed of a GaAlAsP crystal of the conducting type reverse to that of the first cladding layer. The cladding layers disposed on both sides of the active layer have a lower refractivity and a larger band gap than the active layer.

Abstract: A semiconductor laser device has stabilized longitudinal and transverse modes without excess optical noise for a modulated signal generated by mode interaction. The fundamental construction of the semiconductor laser device comprises a structure wherein a first semiconductor layer is sandwiched between second and third semiconductor layers which have a greater band gap and lower index of refraction than the first semiconductor layer. That region of at least one of the second and third semiconductor layers which is remote from the first semiconductor layer corresponds substantially to a radiation region and serves as a light non-absorptive region in the shape of a stripe. A semiconductor layer has portions lying on both sides of the semiconductor layer remote from the first semiconductor layer and has an effective complex refractive-index for laser light discontinuous at both ends of the semiconductor layer remote from the first semiconductor layer.