SEMICONDUCTOR LIGHT-EMITTING MATERIAL AND LIGHT EMITTING DEVICE

Abstract

A semiconductor light-emitting material includes a semiconductor substance including a matrix semiconductor whose constituent atoms are bonded to form a tetrahedral structure, an impurity atom S substituted for an atom in a lattice site of the matrix semiconductor, and an impurity atom I inserted in a interstitial site of the matrix semiconductor, the impurity atom S and the impurity atom I being bonded through charge transfer therebetween in a state that the impurity atom S has an electric charge coincident with that of the constituent atom of the matrix semiconductor and the impurity atom I has an electron configuration of a closed shell structure, in which the semiconductor substance is stretched in a direction of a bond forming the tetrahedral structure.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1A shows an electronic state in a real space in respect of the Γ-point conduction band of silicon;

FIG. 1B schematically shows the directions of changes in conduction band and in valence band caused by stretching of a Si—Si bond;

FIG. 2A shows changes in the band structure in the case of stretching a bulk Si in the <111> direction;

FIG. 2B is a graph showing the relationship between the amount of the Si—Si bond stretching and the ratio of s-orbital component at the bottom of the conduction band at the Γ-point;

FIGS. 3A, 3B, and 3C show the electronic states in a real space in respect of the X-point conduction band, the Γ-point conduction band, and the Γ-point valence band in the energy bands of silicon;

FIGS. 4A, 4B, and 4C schematically show change in energy in the X-point conduction band caused by the FT structure;

FIG. 5 shows the structure of a pendant type FT semiconductor;

FIGS. 6A and 6B are cross-sectional views showing silicon light emitting devices of a vertical type and a lateral type according to embodiments;

FIGS. 7A, 7B, 7C and 7D are cross-sectional views showing a method of forming an active layer including a PF-doped FT-Si according to an embodiment;

FIGS. 8A and 8B are cross-sectional views showing silicon light emitting devices of a vertical type and a lateral type according to another embodiments;

FIG. 9 is a cross-sectional view showing a vertical type silicon light emitting device according to another embodiment;

FIG. 10 is a cross-sectional view showing a lateral type silicon light emitting device according to another embodiment;

FIGS. 11A and 11B are a cross-sectional view and a perspective view, respectively, showing an edge-emitting silicon light emitting device according to a sixth embodiment;

FIGS. 12A and 12B are a cross-sectional view and a perspective view, respectively, showing a surface-emitting silicon light emitting device according to a seventh embodiment;

FIGS. 13A and 13B are a cross-sectional view and a perspective view, respectively, showing a surface-emitting silicon light emitting device according to an eighth embodiment;

FIGS. 14A and 14B are a cross-sectional view and a perspective view, respectively, showing an edge-emitting LD device according to a ninth embodiment;

FIGS. 15A and 15B are a cross-sectional view and a perspective view, respectively, showing a surface-emitting LD device according to a tenth embodiment;

FIG. 16 is a cross-sectional view showing a photoelectric device array according to an eleventh embodiment;

FIG. 17 is a graph showing response characteristics of the LD device in the photoelectric device array according to the eleventh embodiment;

FIG. 18 is a cross-sectional view showing a light receiving-emitting device array according to a twelfth embodiment;

FIG. 19 is a graph showing response characteristics of the LD device included in the light receiving-emitting array according to the twelfth embodiment;

FIG. 20 is a cross-sectional view showing a light-emitting device array according to a thirteenth embodiment;

FIGS. 21A and 21B show the input image and the output image, respectively, of the LD device in the light emitting device array according to the thirteenth embodiment;

FIG. 22 is a perspective view showing an optical device array according to a fourteenth embodiment; and

FIG. 23 is a graph showing response characteristics of the light-receiving device relative to the input signal supplied from the LD device in the optical device array according to the fourteenth embodiment.

Claims

1. A semiconductor light-emitting material, comprising: a semiconductor substance whose constituent atoms are bonded to form a tetrahedral structure which is stretched in a direction of a bond.

2. The material according to claim 1, wherein the constituent atom of the semiconductor substance is silicon, and wherein the material is stretched in a crystal orientation by 1% or more and 12% or less.

3. The material according to claim 1, wherein the material is formed in a substrate made of the semiconductor substance whose constituent atoms are bonded to form the tetrahedral structure, and wherein the substrate is stretched in a <111> direction or a direction equivalent thereto.

4. The material according to claim 1, wherein a second substance different from the semiconductor substance in thermal expansion coefficient or in lattice constant is arranged in a same plane with the semiconductor substance, and wherein the semiconductor substance receives a stress from the second substance so as to be stretched in a <111> direction or a direction equivalent thereto.

5. The material according to claim 1, wherein a second substance different from the semiconductor substance in thermal expansion coefficient or in lattice constant is stacked on the semiconductor substance, and wherein the semiconductor substance receives a stress from the second substance so as to be stretched in a <111> direction or a direction equivalent thereto.

6. A semiconductor light-emitting material, comprising: a semiconductor substance comprising: a matrix semiconductor whose constituent atoms are bonded to form a tetrahedral structure; an impurity atom S substituted for an atom in a lattice site of the matrix semiconductor; and an impurity atom I inserted in a interstitial site of the matrix semiconductor, the impurity atom S and the impurity atom I being bonded through charge transfer therebetween in a state that the impurity atom S has an electric charge coincident with that of the constituent atom of the matrix semiconductor and the impurity atom I has an electron configuration of a closed shell structure, wherein the semiconductor substance is stretched in a direction of a bond forming the tetrahedral structure.

7. The material according to claim 6, wherein pairs of the impurity atom S and the impurity atom I form an ISSI bond.

8. A light emitting device, comprising: an active layer comprising the semiconductor light-emitting material according to claim 1; andan n-electrode and a p-electrode which supply a current to the active layer.

9. The device according to claim 8, further comprising an n-layer formed the active layer and the n-electrode and in contact with the active layer between, and a p-layer formed between the active layer and the p-electrode and in contact with the active layer, wherein the n-layer, the active layer and the p-layer are stacked.

10. The device according to claim 8, further comprising an n-layer formed between the active layer and the n-electrode and in contact with the active layer, and a p-layer formed between the active layer and the p-electrode and in contact with the active layer, wherein the n-layer, the active layer and the p-layer are arranged in a plane.

11. The device according to claim 8, further comprising an antireflection coating formed on one edge surface of the active layer and a reflection coating formed on another edge surface of the active layer.

12. The device according to claim 8, wherein the n-electrode or the p-electrode is arranged as a surface electrode, and further comprising an antireflection coating formed in a portion that is not covered with the surface electrode above the active layer and a reflection coating formed below the active layer in a manner to face the antireflection coating.

13. The device according to claim 8, wherein the n-electrode or the p-electrode is arranged as a surface electrode, and wherein the surface electrode is transparent.

14. The device according to claim 8, further comprising an optical resonator formed of a pair of mirror planes different from each other in reflectivity and arranged to sandwich the active layer therebetween in a plane.

15. The device according to claim 8, further comprising an optical resonator formed of a pair of mirror planes different from each other in reflectivity and arranged to sandwich the active layer therebetween in the vertical direction.

16. A light emitting device, comprising: an n-layer and a p-layer forming a pn junction, each comprising the semiconductor light-emitting material according to claim 1; andan n-electrode connected to the n-layer and a p-electrode connected to the p-layer.