Method for growing a compound semiconductor and a method for producing a semiconductor laser

A method for growing a compound semiconductor layer of Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) on a compound semiconductor substrate by the use of a molecular beam epitaxial apparatus, comprising the steps of:

• providing the substrate having a GaAs layer on an upper surface thereof;
• thermally cleaning an upper surface of the GaAs layer by heating the substrate at a first temperature and by irradiating the GaAs layer with an arsenic molecular beam;
• thermally etching the GaAs layer by heating the substrate at a second temperature which is higher than the first temperature and by irradiating the GaAs layer with a gallium molecular beam and an arsenic molecular beam so as to expose the upper surface of the substrate;
• and
• growing the Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) layer on the upper surface of the substrate.

A method for producing by the use of a molecular beam epitaxial apparatus a semiconductor laser having a substrate, a first layered structure including a double-hetero structure and a GaAs layer, and a second layered structure, the method comprising the steps of:

• growing the first layered structure on the substrate so as to deposit the GaAs layer directly on the double-hetero structure;
• etching the first layered structure into a striped shape so as to expose a surface of the GaAs layer;
• thermally cleaning the exposed surface of the GaAs layer by heating the substrate at a first temperature and by irradiating the GaAs layer with an arsenic molecular beam;
• thermally etching the exposed surface of the GaAs layer by heating the substrate at a second temperature which is higher than the first temperature and by irradiating the GaAs layer with a gallium molecular beam and an arsenic molecular beam so as to expose a surface of the double-hetero structure;
• and
• growing the second layered structure on the upper surface of the first layered structure including the exposed surface of the double-hetero structure.