JP3331591B2 - Light-emitting material, method of manufacturing the same, and light-emitting element using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal silicide light emitting material used in the field of optical interconnection for performing communication by light, a method of manufacturing the same, and a light emitting device using the same.

[0002]

2. Description of the Related Art As a light emitting element on a silicon substrate for optical interconnection, application of a compound semiconductor such as gallium arsenide is a candidate. However, these compound semiconductors have difficulty in producing a structure with few defects on a silicon substrate, and have poor thermal stability. In addition, in the manufacture thereof, it is not possible to cope with only the existing silicon integrated circuit manufacturing process, and it is necessary to add a new manufacturing process, which increases the manufacturing cost. Therefore, a technique for manufacturing a silicon-based light emitting structure that can be manufactured only by a manufacturing process of an existing silicon integrated circuit is desired.

Heretofore, among light-emitting elements manufactured by such a technique, a light-emitting element containing iron silicide, which emits light at a wavelength of about 1.5 μm and is compatible with a quartz optical fiber, has been reported as a light-emitting element which emits light by current injection. (D.Leong, MH
arry, KJReesen, and KPHomewood, "NATURE" Vol.3
87, 12 June 1997, pp686-688). In this light-emitting element, an n-type silicon layer and a p-type silicon layer are stacked on an n-type silicon substrate having a crystal orientation (100) by epitaxial growth, and iron ions are deposited on the p-type silicon layer near the interface of the pn junction on the substrate. After the implantation, annealing is performed so that β-FeS
to form a single crystal layer of i ₂ are made.

[0004]

However, in the light emitting device containing the above-mentioned iron silicide, β-FeSi ₂ is formed not in a dot shape but in a layer shape, and β-FeSi ₂ having good crystallinity can be obtained by ion implantation. Therefore, there is a problem that the external quantum efficiency is about 0.1% and the luminous efficiency is low.
An object of the present invention is to provide a light emitting material having high luminous efficiency and low threshold current. Another object of the present invention is to provide a method for easily and inexpensively producing the above-mentioned light-emitting material, wherein the light-emitting wavelength can be adjusted so as to be compatible with various optical fibers. Another object of the present invention is to
An object is to provide a light-emitting element using the light-emitting material.

[0005]

The invention according to claim 1 is
As shown in FIGS. 1 and 2, a luminescent material in which β-iron silicide semiconductor particles 13 having a particle size of nanometer order are dispersed in a p-type or n-type amorphous silicon 14 or a p-type or n-type amorphous silicon carbide in a dot shape. 10
a and 10b. Β- with particle size of nanometer order
Since the iron silicide semiconductor particles 13 are dispersed in the amorphous silicon 14 or amorphous silicon carbide having a large band gap in a dot-like crystalline state, the injected carriers are confined inside the β-iron silicide semiconductor particles 13. It is desirable that the amorphous silicon 14 or the amorphous silicon carbide is p-type due to the electric conduction characteristics of β-iron silicide.

According to a second aspect of the present invention, a p-type or n-type amorphous silicon, a p-type or n-type amorphous silicon carbide, an insulating amorphous silicon nitride or an amorphous silicon oxide has a particle diameter of β of nanometer order.
-A luminescent material in which metal silicide semiconductor particles other than iron are dispersed in a dot shape. Similar to the invention according to claim 1, metal silicide semiconductor particles other than β-iron having a particle size of nanometer order are p-type or n-type amorphous silicon having a large band gap in a dot-like crystalline state, p-type or n-type. Since the carrier is dispersed in amorphous silicon carbide, insulating amorphous silicon nitride, or amorphous silicon oxide, the injected carriers are confined inside the metal silicide semiconductor particles. Therefore, both of the inventions according to the first and second aspects are compared with a conventional luminescent material in which iron ions are implanted near the interface of a pn junction of a silicon semiconductor by ion implantation and then an annealing treatment is performed to form an iron silicide single crystal layer. Therefore, the luminous efficiency of the luminescent materials of these inventions is remarkably improved.

The invention according to claim 3 is the invention according to claim 2, wherein the metal atoms constituting the metal silicide semiconductor particles other than β-iron dispersed in p-type or n-type amorphous silicon are magnesium and barium. , Chromium, manganese, ruthenium, rhenium, osmium or iridium. The invention according to claim 4 is the invention according to claim 2, wherein metal silicide semiconductor particles other than β-iron dispersed in p-type or n-type amorphous silicon carbide, insulating amorphous silicon nitride or amorphous silicon oxide are used. A light-emitting material in which the constituent metal atoms are magnesium, barium, chromium, manganese, ruthenium, rhenium, osmium, iridium, or calcium.

According to a fifth aspect of the present invention, as shown in FIG. 1, a p-type amorphous silicon layer 14a is formed on an n-type semiconductor substrate 11a.
This is a method for producing a luminescent material in which β-iron silicide semiconductor particles 13 are deposited in dots on a, and a p-type amorphous silicon layer 14a is formed so as to fill the β-iron silicide semiconductor particles 13. The invention according to claim 6 is the invention according to claim 5, wherein the β-iron silicide semiconductor particles 1
This is a method for manufacturing a light emitting material in which the deposition of No. 3 and the formation of the p-type amorphous silicon layer 14a are repeated at least once.

According to a seventh aspect of the present invention, as shown in FIG. 2, a p-type amorphous silicon layer 14a is formed on a p-type semiconductor substrate 11b, and β-iron silicide semiconductor particles are formed on the p-type amorphous silicon layer 14a. 13 are deposited in a dot shape, and a p-type amorphous silicon layer 14a is formed so as to fill the β-iron silicide semiconductor particles 13;
This is a method for manufacturing a light emitting material for forming an n-type amorphous silicon layer 12a on the p-type amorphous silicon layer 14a. The invention according to claim 8 is the invention according to claim 7, wherein the deposition of the β-iron silicide semiconductor particles 13 and the formation of the p-type amorphous silicon layer 14a are repeated at least once, and then the n-type amorphous silicon layer is formed. This is a method for producing a light emitting material for forming the light emitting material 12a.

According to a ninth aspect of the present invention, as shown in FIG. 3 or FIG. 4, a β-iron silicide semiconductor particle 13 having a particle size of nanometer order is formed on an n-type or p-type semiconductor substrate 11a, 11b. Light-emitting element 2 in which light-emitting layers 15 a and 15 b dispersed in a dot shape are formed in silicon 14.
0a and 20b. By using the light emitting material according to claim 1 as the light emitting layers 15a and 15b, light emitting elements 20a and 20b having high light emission efficiency and high light emission decay rate can be obtained.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The β-iron silicide luminescent material or other metal silicide luminescent material of the present invention comprises amorphous silicon (Si), amorphous silicon carbide (SiC).
_X , where 0 <X ≦ 1), insulating amorphous silicon nitride (Si ₃ N _Y , where 0 <Y ≦ 4) or amorphous silicon oxide (SiO _Z , where 0 <Z ≦ 2). Iron or other metal silicide semiconductor particles are dispersed in the form of dots. The amorphous silicon, silicon carbide, silicon nitride or silicon oxide is formed by chemical vapor deposition (hereinafter referred to as CVD).
), And is formed by laminating one or two or more amorphous layers. The β-iron or other metal silicide semiconductor particles dispersed in the amorphous silicon or the like are formed alternately with the amorphous layer into a dot shape having a particle size of nanometer order by the CVD method. By using this CVD method, β-iron or other metal silicide is self-organized and formed in a dot shape.
In the CVD method of the present invention, the metal silicide semiconductor particles are formed into dots by controlling the flow rate of the source gas, the gas ratio, the gas pressure, the deposition time, and the like, as compared with the case where metal silicide is formed by ion implantation. It is easy and can have good crystallinity. For this reason, the luminescent material of the present invention has very few structures that cause non-luminescent centers such as lattice defects and dislocations, and increases luminous efficiency.

By changing the type and particle size of the metal atoms constituting the metal silicide semiconductor particles, it is possible to produce a light emitting device which emits light of a wavelength suitable for various optical fibers used in the field of optical interconnection. When the metal atom is a metal atom constituting metal silicide semiconductor particles other than β-iron dispersed in p-type or n-type amorphous silicon, magnesium, barium,
It is selected from chromium, manganese, ruthenium, rhenium, osmium or iridium. Β in which metal atoms are dispersed in p-type or n-type amorphous silicon carbide, insulating amorphous silicon nitride or amorphous silicon oxide.
In the case where the metal atom constitutes a metal silicide semiconductor particle other than iron, is selected from magnesium, barium, chromium, manganese, ruthenium, rhenium, osmium, iridium or calcium. The particle size of the metal silicide semiconductor particles can be changed by controlling the above manufacturing conditions. Also, the particle size can be adjusted to nanometer order (1 nm to several hundred nm).
This particle size is preferably 1 to 10 in consideration of luminous efficiency.
0 nm. Therefore, the deposition time and temperature of the metal silicide are controlled so that the metal silicide does not form a film. Since the metal silicide semiconductor particles emit light of different wavelengths for each metal atom, a desired metal silicide is selected according to the application. For example, β-iron silicide emits light having a wavelength of about 1.5 μm and is suitable for a quartz optical fiber.

When the substance for confining the β-iron silicide semiconductor particles is a p-type amorphous silicon layer, the luminescent material of the present invention is manufactured by the following two methods. First
Is a method according to claim 5 or claim 6, wherein p is first formed on an n-type semiconductor substrate 11a as shown in FIG.
A type amorphous silicon layer 14a is formed. The p-type amorphous silicon layer 14a may be stacked by CVD, or may be formed by ion-implanting a dopant such as boron, indium, or gallium into the surface of the semiconductor substrate 11a. Then, the p-type amorphous silicon layer 1
Β-iron silicide semiconductor particles 1 by CVD
3 is deposited in a dot shape, and the p-type amorphous silicon layer 14 is filled so as to fill the β-iron silicide semiconductor particles 13.
a is formed. In order to increase the light emission density, it is preferable to repeat the deposition of the β-iron silicide semiconductor particles 13 and the formation of the p-type amorphous silicon layer 14a at least once. In this case, the p-type amorphous silicon layer 14a
And β-iron silicide semiconductor particles 13 are alternately deposited. Thereby, the light emitting layer 15a is formed on the semiconductor substrate 11a.

The second manufacturing method is a method according to claim 7 or claim 8, wherein a p-type amorphous silicon layer 14a is first formed on a p-type semiconductor substrate 11b as shown in FIG. This p-type amorphous silicon layer 14a is formed by CVD.
Or a dopant such as boron, indium, or gallium may be ion-implanted into the surface of the semiconductor substrate 11b. Next, β-iron silicide semiconductor particles 13 are deposited in a dot shape on the p-type amorphous silicon layer 14a by the CVD method, and a p-type amorphous silicon layer 14a is formed so as to fill the β-iron silicide semiconductor particles 13. In order to increase the light emission density, it is preferable to repeat the deposition of the β-iron silicide semiconductor particles 13 and the formation of the p-type amorphous silicon layer 14a at least once. In this case, after alternately depositing the p-type amorphous silicon layer 14a and the metal silicide semiconductor particles 13, the n-type amorphous silicon layer 12a is formed. Thereby, the light emitting layer 15 is formed on the semiconductor substrate 11b.
b is formed.

According to the ninth aspect of the present invention, as shown in FIG. 3, the light emitting layer 15a is formed on the n-type semiconductor substrate 11a.
Further, as shown in FIG. 4, the above-described light emitting layers 15b are formed on the p-type semiconductor substrate 11b. By forming the electrodes 16 and 17 on the upper surface of the light emitting layer 15a or 15b and the lower surface of the semiconductor substrate 11a or 11b, respectively, the light emitting element 20a or 20b is obtained. The semiconductor substrate is preferably a silicon substrate.

[0016]

Next, an embodiment of the present invention will be described with reference to the drawings. In this example, the CV shown in FIG.
A light emitting layer was formed on a silicon substrate under the following conditions using a D apparatus. That is, the first gas introduction pipe 2 is provided in the CVD furnace 20.
First, a second gas introduction pipe 22 and a vacuum exhaust pipe 23 are provided. From the first gas introduction pipe 21, S diluted with nitrogen gas
iH ₄ gas and B ₂ H ₆ gas for dopant are introduced, and FeCl diluted with nitrogen gas is introduced through the second gas introduction pipe 22.
An iron chloride gas mainly containing ₂ and FeCl ₃ is introduced. In the CVD furnace 20, an n-type silicon substrate 11a having a crystal orientation of (100) is held by a substrate holder 24. A reaction furnace 26 is provided before the second gas introduction pipe 22. A filamentous iron wire 27 having a purity of 99.9% or more is accommodated in the reaction furnace 26, and a chlorine gas introduction pipe 28 is provided in the reaction furnace 26.

Next, formation of a light emitting layer by the above-described CVD apparatus will be described. First, the iron wire 27 in the reaction furnace 26 is
When the gas is heated to 00 ° C. and chlorine gas (Cl ₂ ) diluted with nitrogen gas is introduced into the reaction furnace 26 through a chlorine gas introduction pipe 28, the iron wire 27 chemically reacts with chlorine gas to produce FeCl _2.
And an iron chloride gas containing FeCl ₃ as a main component. The iron chloride gas is supplied into the CVD furnace 20 through the second gas introduction pipe 22. On the other hand, SiH ₄ gas diluted with nitrogen gas and B ₂
H ₆ gas is supplied into the CVD furnace 20. First and second
By adjusting the gas supply from the gas inlet pipe, C
In the VD furnace 20, β-iron silicide (FeS
i ₂ ) so that the film formation rate is 0.1 nm / sec or less,
The partial pressures of the SiH ₄ gas and the iron chloride gas are determined.

First, the temperature of the n-type silicon substrate 11a is set to 56
The temperature was lowered to 0 ° C., and the SiH ₄ gas diluted with nitrogen gas and the B ₂ H ₆ gas for dopant were supplied from the first gas introduction pipe 21 to CV.
It was introduced into a D furnace 20 to form a highly doped p-type amorphous silicon layer 14a. Next, after heating the n-type silicon substrate 11a in the CVD furnace 20 to 750 to 850 ° C,
A gas having a predetermined flow ratio is introduced from the first and second gas introduction pipes 21 and 22, and as shown in FIG.
1a is formed on the highly doped p-type amorphous silicon layer 14a.
₂ ) Particles 13 were formed.

Next, the temperature of the n-type silicon substrate 11a is lowered again to 560 ° C., and the SiH ₄ gas diluted with nitrogen gas and the B ₂ H ₆ gas for the dopant are supplied from the first gas introduction pipe 21 into the CVD furnace 20. To the β-iron silicide particles 13
To form a highly doped p-type amorphous silicon layer 14a. Here, the p-type amorphous silicon layer was deposited to 20 Å or more. Then, β-
The deposition of the iron silicide particles 13 and the deposition of the highly doped p-type amorphous silicon layer 14a were repeated four times to form the light emitting layer 15a as shown in FIG.

After the luminescent material shown in FIG. 1 is prepared, the silicon substrate 11a is taken out of the CVD furnace 20, and a Au thin film is formed on the upper surface of the uppermost p-type amorphous silicon layer 14a by using a vacuum evaporation apparatus (not shown). Electrode 16
And an electrode 17 made of an Au—Sb alloy film is formed on the lower surface of the silicon substrate 11a.
I got A forward bias was applied to the electrodes 16 and 17 of the obtained light emitting device 20a, and electroluminescence (EL) was measured. FIG. 6 shows the result. As is clear from FIG. 6, electroluminescence having a peak at about 1.5 μm, which is an emission wavelength suitable for a quartz optical fiber, was confirmed.

[0021]

As described above, the metal silicide luminescent material of the present invention has a structure in which metal silicide semiconductor particles having a particle size of nanometer order are dispersed in amorphous silicon in the form of dots. The threshold current can be reduced. In addition, since the metal silicide is self-assembled using a conventional simple process called a chemical vapor deposition method, there is an advantage that a light emitting material can be manufactured at low cost. In addition, since the emission wavelength can be adjusted by changing the particle size of the metal silicide semiconductor particles, it is necessary to create a light-emitting element that emits a wavelength suitable for various optical fibers used in the field of optical interconnection. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a configuration of a light emitting material manufactured by a first manufacturing method of the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a configuration of a light emitting material manufactured by a second manufacturing method of the present invention.

FIG. 3 is a schematic cross-sectional view illustrating a configuration of a light emitting element using a light emitting material manufactured by the first manufacturing method of the present invention.

FIG. 4 is a schematic cross-sectional view illustrating a configuration of a light emitting element using a light emitting material manufactured by a second manufacturing method of the present invention.

FIG. 5 is a configuration diagram of a CVD apparatus used for manufacturing the light emitting material of the present invention.

FIG. 6 is a diagram showing the emission wavelength and emission intensity of the light-emitting element.

[Explanation of symbols]

 10a, 10b β-iron silicide light emitting material 11a n-type semiconductor substrate (n-type silicon substrate) 11b p-type semiconductor substrate (p-type silicon substrate) 12a n-type amorphous silicon layer 13 β-iron silicide semiconductor particles 14 p-type amorphous silicon 14a P-type amorphous silicon layer 15a, 15b Light emitting layer 16, 17 Electrode 20a, 20b Light emitting element

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-317086 (JP, A) WO 98/18167 (WO, A1) WO 93/9564 (WO, A1) Jan. J. Appl. Phys. Part 2, 36 [9A / B], p. L1225-L1228J. Appl. Phys. , 58 [7], p. 2696-2703 Nature, 387 (1997) p. 656-688 Appl. Phys. Lett. , 59 [17] (1991), p. 2145-2147 Nucl. Inst. & Meth. In Phys. Res. Sec. B, 84 [2] (1994), p. 168-171 (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 33/00 H01S 5/00-5/50 JICST file (JOIS)

Claims (9)

(57) [Claims] 1. A p-type or n-type amorphous silicon
(14) A light emitting material in which β-iron silicide semiconductor particles (13) having a particle size of nanometer order are dispersed in a dot form in p-type or n-type amorphous silicon carbide. 2. Metallic silicide semiconductor particles other than β-iron having a particle size on the order of nanometers in p-type or n-type amorphous silicon, p-type or n-type amorphous silicon carbide, insulating amorphous silicon nitride or amorphous silicon oxide. A luminescent material dispersed in the form of dots. 3. Metal particles constituting metal silicide semiconductor particles other than β-iron dispersed in p-type or n-type amorphous silicon are magnesium, barium, chromium,
The luminescent material according to claim 2, wherein the luminescent material is manganese, ruthenium, rhenium, osmium or iridium. 4. A metal atom constituting metal silicide semiconductor particles other than β-iron dispersed in p-type or n-type amorphous silicon carbide, insulating amorphous silicon nitride or amorphous silicon oxide is magnesium, barium,
The luminescent material according to claim 2, which is chromium, manganese, ruthenium, rhenium, osmium, iridium, or calcium. 5. A p-type amorphous silicon layer (14a) is formed on an n-type semiconductor substrate (11a), and β-iron silicide semiconductor particles (13) are formed on the p-type amorphous silicon layer (14a).
Are deposited in the form of dots, and the β-iron silicide semiconductor particles
(13) Fill p-type amorphous silicon layer (14a)
A method for producing a luminescent material for forming 6. The method according to claim 5, wherein the deposition of the β-iron silicide semiconductor particles (13) and the formation of the p-type amorphous silicon layer (14a) are repeated at least once. 7. A p-type amorphous silicon layer (14a) is formed on a p-type semiconductor substrate (11b), and β-iron silicide semiconductor particles (13) are formed on the p-type amorphous silicon layer (14a).
Are deposited in the form of dots, and the β-iron silicide semiconductor particles
(13) Fill p-type amorphous silicon layer (14a)
Forming a n-type amorphous silicon layer (12a) on the p-type amorphous silicon layer (14a). 8. After the deposition of the β-iron silicide semiconductor particles (13) and the formation of the p-type amorphous silicon layer (14a) are repeated at least once, the n-type amorphous silicon layer (1) is formed.
The method for producing a luminescent material according to claim 7, wherein 2a) is formed. 9. On the n-type or p-type semiconductor substrate (11a, 11b), β-iron silicide semiconductor particles (13) having a particle size of nanometer order are dispersed in the form of dots in p-type amorphous silicon (14). A light emitting element on which light emitting layers (15a, 15b) are formed.