Method for growth of crystal surfaces and growth of heteroepitaxial single crystal films thereon

• US 6,165,874 A
• Filed: 12/16/1998
• Issued: 12/26/2000
• Est. Priority Date: 07/03/1997
• Status: Expired due to Fees

• Current Assignee: National Aeronautics and Space Administration US Government As Represented By The Administrator of The
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Matus, Lawrence G., Larkin, David J., Neudeck, Philip G., Powell, J. Anthony
• Primary Examiner(s): Elms, Richard
• Assistant Examiner(s): SMITH, BRADLEY
• Application Number:
  US09/252,623
• Time in Patent Office: 741 Days
• Field of Search: 438/607, 438/478, 438/503, 438/504, 438/931, 438/483, 117/95, 117/101, 117/105, 117/106
• US Class Current: 438/478
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 25/18 characterised by the substrate
• CPC Class Codes: C30B 29/36 Carbides
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: C30B 29/406 Gallium nitride
• CPC Class Codes: H01L 21/02378 Silicon carbide
• CPC Class Codes: H01L 21/0243 Surface structure
• CPC Class Codes: H01L 21/02433 Crystal orientation
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/02634 Homoepitaxy
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041
• CPC Class Codes: H01L 33/0054 for devices with an active region comprising only group IV elements
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: Y10S 438/931 Silicon carbide semiconductor

Abstract

A method of growing atomically-flat surfaces and high quality low-defect crystal films of semiconductor materials and fabricating improved devices thereon. The method is also suitable for growing films heteroepitaxially on substrates that are different than the film. The method is particularly suited for growth of elemental semiconductors (such as Si), compounds of Groups III and V elements of the Periodic Table (such as GaN), and compounds and alloys of Group IV elements of the Periodic Table (such as SiC).

Claims

1. A method of producing single-crystal atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to said at least one growth plane orientation of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and to remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation; and

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane.

2. The method according to claim 1, wherein said single-crystal material is selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.

3. The method according to claim 2, wherein said selected material has a cubic crystal structure.

4. The method according to claim 3, wherein said at least one growth plane orientation is within one (1) degree of the (111) plane.

7. The method according to claim 1, wherein said multiple heteroepitaxial films comprise adjacent layers that are brought together with a buffer layer that reduces the stress between adjacent layers.

8. The method according to claim 7, wherein said buffer layer is a material selected from the group comprising AlN, AlGaN, and GaN.

5. A method of producing multiple heteroepitaxial films of atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to said at least one growth plane orientation of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation;

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(g) depositing a desired heteroepitaxial film selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table on said homoepitaxial film under predetermined conditions that preferably cause two-dimensional nucleation accompanied by step-flow growth of said desired heteroepitaxial film;

(h) continuing said depositing of said step (g) of said heteroepitaxial film until a desired thickness is obtained;

(i) continuing the growth of the said heteroepitaxial film under selected conditions so as to provide a step flow growth while suppressing two-dimensional nucleation;

(j) continuing said deposition of said heteroepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(l) repeating step (g);

(m) repeating step (h);

(n) repeating step (i);

(o) repeating step (j); and

(p) repeating steps (l), (m), (n), and (o) until desired multiple heteroepitaxial film structure is obtained.

6. The method according to claim 5, wherein said substrate is of a material selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.

9. The method according to claim 5, wherein the said heteroepitaxial film is one of a binary, a ternary, and quaternary semiconductor compound of the Group III and Group V elements.

10. A method of producing a semiconductor device having single-crystal atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to said at least one growth plane orientation of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation; and

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane.

11. The method according to claim 10, wherein said substrate is of a material selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.

12. A method of producing a semiconductor device having a heteroepitaxial film of atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to said at least one growth plane orientation of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation;

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(g) depositing a desired heteroepitaxial film selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table on said homoepitaxial film under predetermined conditions that preferably cause two-dimensional nucleation accompanied by step-flow growth of said desired heteroepitaxial film; and

(h) continuing said depositing of said step (f) of said heteroepitaxial film until a desired thickness is obtained.

13. The method according to claim 12, wherein said substrate is of a material selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.

14. A method of producing a semiconductor device having multiple heteroepitaxial films of atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to said at least one growth plane orientation of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation;

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(g) depositing a desired heteroepitaxial film selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table on said homoepitaxial film under predetermined conditions that preferably cause two-dimensional nucleation accompanied by step-flow growth of said desired heteroepitaxial film;

(h) continuing said depositing of said step (g) of said heteroepitaxial film until a desired thickness is obtained;

(i) continuing the growth of the said heteroepitaxial film under selected conditions so as to provide a step flow growth while suppressing two-dimensional nucleation;

(j) continuing said deposition of said heteroepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(k) repeating step (g);

(l) repeating step (h);

(m) repeating step (i);

(n) repeating step (j); and

(o) repeating steps (k), (l), (m), and (n) until desired multiple heteroepitaxial film structure of said semiconductor device is obtained.

15. The method according to claim 14, wherein said substrate is of a material selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.

16. A method of producing a laser diode having multiple heteroepitaxial films of atomically-flat surfaces on a single-crystal substrate, said method comprising the steps of:

(a) choosing a single-crystal substrate material which exhibits the property that the material contains at least one growth plane orientation whereby under selected growth conditions the growth rate due to step-flow growth is greater than at least one hundred (100) times the growth rate due to growth involving two-dimensional nucleation;

(b) preparing a planar growth surface on said substrate that is parallel to within a predetermined angle relative to a selected crystal plane of said substrate;

(c) removing material in said substrate so as to define at least one selected separated area having boundaries;

(d) treating said substrate so as to remove any sources of unwanted crystal nucleation and remove any unwanted sources of steps;

(e) depositing a homoepitaxial film over said at least one selected separated area under selected conditions so as to provide a step-flow growth while suppressing two-dimensional nucleation;

(f) continuing said deposition of said homoepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(g) depositing a desired heteroepitaxial film selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table on said homoepitaxial film under predetermined conditions that preferably cause two-dimensional nucleation accompanied by step-flow growth of said desired heteroepitaxial film;

(h) continuing said depositing of said step (g) of said heteroepitaxial film until a desired thickness is obtained;

(i) continuing the growth of the said heteroepitaxial film under selected conditions so as to provide a step flow growth while suppressing two-dimensional nucleation;

(j) continuing said deposition of said heteroepitaxial film until said step-flow growth obtains an atomically-flat epitaxial film surface on each of said at least one separated area where said atomically-flat surface is parallel to said selected crystal plane;

(k) repeating step (g);

(l) repeating step (h);

(m) repeating step (i);

(n) repeating step (j); and

(o) repeating steps (k), (l), (m), and (n) until desired multiple heteroepitaxial film structure for said laser diode is obtained.

17. The method according to claim 16, wherein said substrate is of a material selected from the group comprising elemental semiconductors, compounds of Group III and Group V elements of the Periodic Table and compounds and alloys of the Group IV elements of the Periodic Table.