Semiconductor device

• US 7,816,702 B2
• Filed: 10/03/2008
• Issued: 10/19/2010
• Est. Priority Date: 10/05/2007
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Uchiyama, Hiroyuki, Aoki, Masahiro, Saito, Shinichi, Yamamoto, Jiro, Sakuma, Noriyuki, Arimoto, Hideo
• Primary Examiner(s): Smith; Zandra
• Assistant Examiner(s): Patton; Paul E
• Application Number:
  US12/245,077
• Publication Number:
  US 20090090925A1
• Time in Patent Office: 746 Days
• Field of Search: 257/98, 257/E33.002, 257/E33.013, 257/E33.015
• US Class Current: 257/98
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 2302/00 Amplification / lasing wavelength
• CPC Class Codes: H01S 5/0424 lateral current injection
• CPC Class Codes: H01S 5/04257 having positive and negative electrodes on the same side of the substrate
• CPC Class Codes: H01S 5/12 the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers comprising a photonic bandgap structure H01S5/11; surface-emitting lasers H01S5/18
• CPC Class Codes: H01S 5/1237 Lateral grating, i.e. grating only adjacent ridge or mesa
• CPC Class Codes: H01S 5/125 Distributed Bragg reflector [DBR] lasers
• CPC Class Codes: H01S 5/18341 Intra-cavity contacts
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/3004 employing a field effect structure for inducing charge-carriers, e.g. FET
• CPC Class Codes: H01S 5/3427 in IV compounds

Abstract

There are a silicon laser device having a IV-group semiconductor such as silicon or germanium equivalent to the silicon as a basic constituent element on a substrate made of the silicon, and the like by a method capable of easily forming the silicon laser device by using a general silicon process, and a manufacturing method thereof. The silicon laser device is an ultrathin silicon laser that includes a first electrode unit injecting electrons, a second electrode unit injecting holes, a light emitting unit electrically connected to the first electrode unit and the second electrode unit, wherein the light emitting unit is made of single-crystal silicon and has a first surface (top surface) and a second surface (bottom surface) opposed to the first surface, a waveguide made of a first dielectric, which is disposed in the vicinity of the light emitting unit, by setting surface directions of the first and second surfaces as a surface (100) and thinning a thickness of the light emitting unit in a direction perpendicular to the first and second surfaces, and a mirror formed by alternately adjoining the first dielectric and a second dielectric.

Claims

1. The semiconductor device comprising on a substrate, a first electrode for injecting electrons:

a second electrode for injecting holes;

a light emitting unit electrically connected to the first and second electrodes and emitting light by being injected with the electrons and holes by applying voltages to both electrodes;

a mirror having a function of reflecting the light emitted from the light emitting unit,

wherein the light emitting unit includes a thin film installed on the substrate and a first insulating film having a first permittivity, which is installed on the thin film,

the mirror is formed by periodically and alternately disposing a plurality of second insulating films having a second permittivity different from the first permittivity and a plurality of third insulating films having a third permittivity different from the second permittivity on the first insulating film to be opposed to each other by a predetermined gap,

the film thickness of the thin film is thinner than those of the first and second electrodes, and

wherein the thin film, and both the first electrode and the second electrode are made of a IV-group semiconductor.

2. The semiconductor device according to claim 1, wherein the film thickness of the thin film is 10 nm or less.

3. The semiconductor device according to claim 1, wherein the IV-group semiconductor has a single-crystal structure and is made of silicon, a surface direction of a surface of the silicon being a surface (100) or a surface direction equivalent to the surface (100).

4. The semiconductor device according to claim 1, wherein the IV-group semiconductor has the single-crystal structure and is made of germanium, a surface direction of a surface of the germanium being a surface 111 or a surface direction equivalent to the surface 111.

5. The semiconductor device according to claim 1, further comprising:

a connector for connecting the light emitting unit and the first electrode or the second electrode to each other,

wherein the film thickness of the connector is thicker than that of the light emitting unit and thinner than those of the first and second electrodes, and

the light emitting unit, the connector, and both the first electrode and the second electrode are made of the IV-group semiconductor.

6. The semiconductor device according to claim 3, wherein the first insulating film is a silicon dioxide film.

7. The semiconductor device according to claim 6, wherein the second insulating film is nitride silicon and the third insulating film is silicon dioxide.

8. The semiconductor device according to claim 1, wherein first impurities having a first conductive type are added to the first electrode,

second impurities having a second conductive type different from the first conductive type are added to the second electrode,

the concentration of first impurities added to the light emitting unit is lower than that of the first impurities added to the first electrode, and

the concentration of second impurities added to the light emitting unit is lower than that of the second impurities added to the second electrode.

9. The semiconductor device comprising on a substrate, a first electrode for injecting electrons;

a second electrode for injecting holes;

a light emitting unit electrically connected to the first and second electrodes and emitting light by being injected with the electrons and holes by applying voltages to both electrodes;

a mirror having a function of reflecting the light emitted from the light emitting unit,

wherein the light emitting unit includes a thin film installed on the substrate and a first insulating film having a first permittivity, which is installed on the thin film,

the mirror is formed by periodically and alternately disposing a plurality of second insulating films having a second permittivity different from the first permittivity and a plurality of third insulating films having a third permittivity different from the second permittivity on the first insulating film to be opposed to each other by a predetermined gap,

the film thickness of the thin film is thinner than those of the first and second electrodes, and

wherein the light emitting unit is installed between the first electrode and the second electrode which are installed to be opposed to each other,

the mirror is installed in a first direction on the light emitting unit parallel to the first and second electrodes, and

a laser beam emitted from the light emitting unit and amplified by the mirror is outputted in the first direction.

10. The semiconductor device further comprising:

on a substrate, a first electrode for injecting electrons;

a second electrode for injecting holes;

a light emitting unit electrically connected to the first and second electrodes and emitting light by being injected with the electrons and holes by applying voltages to both electrodes;

a mirror having a function of reflecting the light emitted from the light emitting unit,

wherein the light emitting unit includes a thin film installed on the substrate and a first insulating film having a first permittivity, which is installed on the thin film,

the mirror is formed by periodically and alternately disposing a plurality of second insulating films having a second permittivity different from the first permittivity and a plurality of third insulating films having a third permittivity different from the second permittivity on the first insulating film to be opposed to each other by a predetermined gap,

the film thickness of the thin film is thinner than those of the first and second electrodes, and

an opening portion having a film thickness thinner than the film thickness of the substrate, which is formed on a second main surface of the substrate opposed to a first main surface of the substrate on which the light emitting unit is installed,

wherein the opening portion is disposed so that at least a part of the opening portion exists on a virtual line on which a region where the light emitting unit is installed extends to the substrate.

11. The semiconductor device according to claim 10, wherein an electrode having radiation performance is installed through a dielectric installed on the surface of the opening portion.