Abstract: A thermal decomposition cell for producing a molecular beam from a material gas, includes: a crucible maintained at a given temperature necessary for thermal decomposition of the material gas which is effused in the crucible in a given direction; and a thermal decomposition baffle provided in the crucible and heated to a given temperature necessary for thermal decomposition of the material gas for producing the molecular beam by thermal-decomposing of the material gas such that the material gas is baffled in substantially all directions, the thermal decomposition baffle being made of a given metal to cause the thermal decomposition of the material gas. The thermal decomposition baffle may comprise a fiber or a cloth made of the metal loaded in the crucible.

Abstract: A method for fabricating a semiconductor laser device wherein a first clad layer is formed on a GaAs monocrystal substrate of one conductivity type. The first clad layer is made of a compound semiconductor of one conductivity type represented by the formula, (Al.sub.x Ga.sub.1-x).sub.0.5 In.sub.0.5 P, wherein 0.4 .ltoreq.X.ltoreq.1. Then, an active layer of a compound semiconductor of the formula. (Al.sub.y Ga.sub.1-y).sub.0.5 In.sub.0.5 P, wherein 0.ltoreq.y.ltoreq.0.35 is formed on the first clad layer, on which a second clad layer of a compound semiconductor of the other conductivity type represented by the formula defined with respect to the first clad layer. At least one of the first and second clad layers is epitaxially grown at a rate of not larger than 0.5 .mu.m/hour sufficient to form a monolayer superlattice structure therein and the active layer is epitaxially grown at a rate of not less than 2.0 .mu.m/hour.

Abstract: A semiconductor laser device which comprises a monocrystal substrate of consisting essentially of Si.sub.a Ge.sub.1-a, wherein 0.ltoreq.a.ltoreq.0.25, and a compound semiconductor layer which is formed on one side of the substrate and is lattice-matched with the substrate. The compound semiconductor layer includes an Al-free active layer made of Ga.sub.b In.sub.1-b P wherein 0.51<b.ltoreq.0.64 and the first and second clad layers sandwiching the active layer therebetween wherein said first clad layer is formed on the one side of the substrate. The first and second clad layer are each made of (Al.sub.o Ga.sub.1-o).sub.d In.sub.1-d P, wherein 0.4.ltoreq.c.ltoreq.1 and 0.51<d.ltoreq.0.64.

Abstract: A semiconductor light-emitting device comprising a substrate formed of GaAs, a cladding layer formed of (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P and an active layer formed of Ga.sub.y In.sub.1-y P (0.5.ltoreq.y.ltoreq.1) or Ga.sub.y In.sub.1-y P (0.ltoreq.y.ltoreq.0.5), said cladding layer having its composition represented by (Al.sub.x Ga.sub.1-x).sub.0.5 In.sub.0.5 P ((0.ltoreq.x.ltoreq.1), lattice-matched to said GaAs substrate, and said cladding layer having a band-gap size made larger by at least 0.25 eV than said active layer. The device can attain an oscillation wavelength of 0.67 .mu.m or less or from 0.68 .mu.m to 0.78 .mu.m.