Metamorphic long wavelength high-speed photodiode

A method for fabricating a semiconductor device upon a substrate, said method comprising the steps of:

• forming a grading layer upon a (100) nominally on orientation substrate, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon.

A method for fabricating a semiconductor device upon a substrate, said method comprising the steps of:

• forming a grading layer upon said substrate utilizing MOCVD, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon.

A method for fabricating a semiconductor device upon a GaAs substrate, said method comprising the steps of:

• forming a grading layer upon said GaAs substrate, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said GaAs substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon.

A method for fabricating a semiconductor device upon a GaAs substrate, said method comprising the steps of:

• forming a grading layer upon said GaAs substrate utilizing MOCVD, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said GaAs substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon.

A method for fabricating a semiconductor device upon a GaAs substrate, said method comprising the steps of:

• forming a grading layer upon said GaAs substrate utilizing MOCVD, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said GaAs substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon;
• and
• wherein said GaAs substrate comprises a (100) nominally on orientation substrate.

A method for fabricating a semiconductor device upon a GaAs substrate, said method comprising the steps of:

• forming a grading layer upon said GaAs substrate utilizing MOCVD, wherein said grading layer grades a substrate lattice constant past said lattice constant utilized for said semiconductor device;
• forming an intermediate layer, wherein said intermediate layer comprises a lattice constant greater than a lattice constant utilized for said semiconductor device;
• forming an inverse grading layer which grades from said lattice constant of said intermediate layer to said lattice constant utilized for said semiconductor device;
• annealing said grading layer to isolate dislocated material created as a result of forming said grading layer from said GaAs substrate;
• and
• creating a strained layer superlattice to further isolate dislocations from said semiconductor device formed thereon, wherein said GaAs substrate comprises a (100) nominally on orientation substrate;
• and
• wherein each of said layers are formed on said GaAs substrate utilizing Debye length doping.