Semiconductor optical device with nanowhiskers

• US 5,332,910 A
• Filed: 11/30/1993
• Issued: 07/26/1994
• Est. Priority Date: 03/22/1991
• Status: Expired due to Term

• Current Assignee: Opnext Japan, Inc. (Lumentum Holdings Inc.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Haraguchi, Keiichi, Masuhara, Toshiaki, Morgan, Gerard P., Yazawa, Masamits, Ogawa, Kensuke, Yamaguchi, Ken, Hiruma, Kenji, Usagawa, Toshiyuki, Katsuyama, Toshio, Kakibayashi, Hiroshi
• Primary Examiner(s): MINTEL, WILLIAM A
• Application Number:
  US08/159,343
• Time in Patent Office: 238 Days
• Field of Search: 257/14, 257/17, 257/22, 257/21, 257/13, 257/88, 257/90, 257/95, 257/89, 257/443, 257/465, 257/466, 257/618, 257/623, 257/81, 257/82, 257/93, 257/91, 372/48, 372/45, 372/46
• US Class Current: 257/13
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/4202 for coupling an active element with fibres without intermediate optical elements, e.g. fibres with plane ends, fibres with shaped ends, bundles
• CPC Class Codes: H01L 33/0062 for devices with an active region comprising only III-V compounds
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01S 3/06708 Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering optical fibres as passive waveguides G02B6/02
• CPC Class Codes: H01S 5/0028 Laser diodes used as detectors
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/04253 having specific optical properties, e.g. transparent electrodes
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/04256 characterised by the configuration
• CPC Class Codes: H01S 5/0608 controlled by light, e.g. optical switch
• CPC Class Codes: H01S 5/1042 Optical microcavities, e.g. cavity dimensions comparable to the wavelength
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/1228 DFB lasers with a complex coupled grating, e.g. gain or loss coupling
• CPC Class Codes: H01S 5/183 having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]
• CPC Class Codes: H01S 5/223 Buried stripe structure H01S5/227 takes precedence
• CPC Class Codes: H01S 5/3202 grown on specifically orientated substrates, or using orientation dependent growth
• CPC Class Codes: H01S 5/3412 quantum box or quantum dash
• CPC Class Codes: H01S 5/4006 Injection locking
• CPC Class Codes: H01S 5/4031 Edge-emitting structures
• CPC Class Codes: H01S 5/4056 : emitting light in more than one direction
• CPC Class Codes: H01S 5/423 : having a vertical cavity
• CPC Class Codes: H01S 5/5045 : the arrangement having a frequency filtering function

Abstract

A semiconductor light-emitting device includes a plurality of semiconductor rods, each of which has a pn junction. The semiconductor rods are formed on a semiconductor substrate such that the plurality of semiconductor rods are arranged at a distance substantially equal to an integer multiple of the wavelength of light emitted from the semiconductor rod. With such devices, various novel optical devices such as a micro-cavity laser of which the threshold current is extremely small and a coherent light-emitting device having no threshold value can be realized.

Claims

1. A semiconductor optical device comprising:

a semiconductor substrate;

a plurality of semiconductor nanowhiskers each having a pn junction, formed on a main surface of said semiconductor substrate in the direction substantially perpendicular to said main surface, said plurality of semiconductor nanowhiskers each having a first conductivity type region and a second conductivity type region;

a first electrode electrically connected with said first conductivity type regions of said semiconductor nanowhiskers; and

a second electrode electrically connected with said second conductivity type regions of said semiconductor nanowhiskers;

wherein at least a portion of said plurality of semiconductor nanowhiskers are arranged at substantially equal distances; and

wherein desired semiconductor nanowhiskers can be selectively operated by selectively applying power or potential to the desired semiconductor nanowhiskers,

2. A semiconductor optical device according to claim 1, wherein a portion of said plurality of semiconductor nanowhiskers are arranged at a first distance and the remainder of said semiconductor nanowhiskers are arranged at a second distance which is different from the first distance.

3. A semiconductor optical device according to claim 1, wherein said semiconductor nanowhiskers are single-crystalline nanowhiskers grown on the surface of said semiconductor substrate by epitaxial growth.

4. A semiconductor optical device according to claim 3, wherein diameters of said semiconductor nanowhiskers periodically change according to the position along the length of said semiconductor nanowhiskers.

5. A semiconductor optical device according to claim 1, wherein the distance between said semiconductor nanowhiskers adjoining each other is equal to an integral multiple of one-half of a wavelength of light emitted from said semiconductor nanowhiskers.

6. A semiconductor optical device according to claim 5, wherein the distance between said semiconductor nanowhiskers adjoining each other is substantially different from the wavelength of second light emitted in the direction different from the direction of said light.

7. A semiconductor optical device according to claim 1, wherein an i-type region is sandwiched between the p-type regions and n-type regions of said semiconductor nanowhiskers.

8. A semiconductor optical device according to claim 1, wherein said semiconductor nanowhiskers are formed of the same material as that of said semiconductor substrate.

9. A semiconductor optical device according to claim 8, wherein said material is GaAs.

10. A semiconductor optical device according to claim 1, wherein said semiconductor substrate and said semiconductor nanowhiskers are formed of different materials.

11. A semiconductor optical device according to claim 10, wherein said semiconductor substrate is formed of GaAs and said semiconductor nanowhiskers include GaAlAs.

12. A semiconductor optical device according to claim 11, wherein said semiconductor nanowhiskers further include InGaAs.

13. A semiconductor optical device according to claim 10, wherein said semiconductor substrate is formed of InP and said semiconductor nanowhiskers include InGaAs.

14. A semiconductor optical device according to claim 1, wherein diameters of said semiconductor nanowhiskers on said semiconductor substrate are not larger than 1,000 nm.

15. A semiconductor optical device according to claim 1, wherein the crystalline orientation of said semiconductor nanowhiskers in a longitudinal direction is (111).

16. A semiconductor optical device according to claim 5, wherein said plurality of semiconductor nanowhiskers are arranged one-dimensionally on the surface of said semiconductor substrate.

17. A semiconductor optical device according to claim 5, wherein said plurality of semiconductor nanowhiskers are arranged two-dimensionally on the surface of said semiconductor substrate.

18. A semiconductor optical device according to claim 17, wherein said plurality of semiconductor nanowhiskers are arranged in a regular polygon configuration on the surface of said semiconductor substrate.

19. A semiconductor optical device according to claim 1, wherein said first electrode is formed on a rear surface of said semiconductor substrate.

20. A semiconductor optical device according to claim 1, wherein said first electrode is formed on said main surface of said semiconductor substrate.

21. A semiconductor optical device according to claim 1, wherein said second electrode is connected with upper edge portions of said semiconductor nanowhiskers.

22. A semiconductor optical device according to claim 21, wherein an insulating film is disposed between said semiconductor substrate and said second electrode.

23. A semiconductor optical device according to claim 1, wherein a plurality of line-shaped second electrodes are connected with said second conductivity type regions of desired portions of a plurality of said semiconductor nanowhiskers.

24. A semiconductor optical device according to claim 23, wherein a plurality of line-shaped first electrodes are disposed substantially perpendicular with respect to said first electrode on the main surface of said semiconductor substrate in contact with said first conductivity type regions of desired portions of a plurality of said semiconductor nanowhiskers.