JPH04297077A - P-type ii-vi mixed crystal semiconductor and manufacture thereof, and light emitting element - Google Patents

Abstract

PURPOSE:To obtain a method for controlling a p-type conductivity and an efficient light emitting element by the method by adding oxygen to ZnSxSe1-x (0<=x<=1) mixed crystal semiconductor of a light emitting element material of a visible and near ultraviolet light bands. CONSTITUTION:A p-type II-VI mixed crystal semiconductor composed of ZnSxSe1-x (0<x<1) containing oxygen as an acceptor dopant. As a light emitting element, a clad layer 42 (n-type ZnSxSe1-x), an active layer 43 (n-type ZnSxSe1-x 44 (p-type ZnSxSe1-x), and a clad layer 45 are formed on a substrate 41.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a p-type mixed crystal semiconductor ZnSx Se1-x (0
<x<1), its manufacturing method, and a light-emitting device in the visible or near ultraviolet light range that includes the semiconductor as a light-emitting layer and a cladding layer.

0002

[Prior art] II-VI group compound mixed crystal semiconductor ZnSx
Se1-x (0<x<1) has an optical bandgap energy value that changes due to changes in the mixed crystal composition (x).
It changes from 2.7 eV to 3.6 eV and has a direct transition type band structure for all
) is attracting attention as a material. The advantage of using the above mixed crystal semiconductor as a light-emitting device material is that the light-emitting layer can be formed with any composition x (
0<x<1), and the active layer is sandwiched between mixed crystal layers (working as cladding layers) larger than the above x value. The point is that it is possible to realize LED and LD elements with high efficiency and long life, as in the case of the -V group mixed crystal semiconductor AlGaAs system.

As mentioned above, ZnSx Se1-x (0<x<1) mixed crystal semiconductors have advantages as materials for light-emitting devices in the visible or near-ultraviolet region, and so far, high-quality semiconductors have been produced by epitaxial growth. Research on crystalline film formation technology is actively underway.

[0004] However, a major problem with this mixed crystal semiconductor crystal is control of its conduction type, and so far mixed crystal semiconductors showing n-type conduction, ZnSx Se1-x (0<x<1)
has been realized, but there has been little success in converting it to p-type. Conventionally, in order to make the p-type, Na, Li, N
etc. have been attempted as acceptor dopants, but at the current stage, the hole concentration P≧1×
p-type mixed crystal film (ZnSx Se1
-x: 0<x<1) is not obtained. Reasons why the acceptor impurity cannot achieve sufficient p-type conversion as a practical device include low solid solubility in the mixed crystal and the occurrence of defects due to doping. Among the above acceptor dopants, Li is 1×1015c
Li atoms have a solid solubility of m-3 or higher and are being researched as a useful dopant for p-type conductivity, but Li atoms are unstable in solid crystals and are susceptible to current flow and the associated heat. Due to generation, there is a big problem of movement through the crystal.

As mentioned above, the elemental materials of the present invention are the mixed crystal semiconductor ZnSx Se1-x (0<x<1), the binary compound semiconductors ZnSe (corresponding to x=0) and ZnS (x=0).
1), whereas the practical level semiconductor laser (L
D) and have great advantages for realizing junction-type light emitting diode devices (■ Possible to form photoactive layer and cladding layer, ■ ZnSe
However, hardening of the crystal occurs due to the solid solution of S,
Defects that cause deep luminescent centers are less likely to form;
), but a major issue is that p-type technology for manufacturing practical devices has not yet been developed.

It has also become clear that oxygen atoms act as acceptors in ZnSe, and oxygen has been added to ZnSe for the purpose of p-type conduction using the MBE method (for example, K. Akimoto et. al. Phys.
Rev B 39 (1989) 3138). but,
In this method, oxygen is used as a solid raw material, zinc oxide (ZnO).
ZnO, Zn, O, O3
Various molecular beams such as these were generated, and there were major problems in the controllability and reproducibility of the amount of oxygen added. Further, this oxygen addition caused deterioration of crystallinity, and the activation rate of oxygen acceptors was as low as 10% or less.

[0007] Also, metal organic vapor phase epitaxy (hereinafter referred to as MOVPE)
In vapor phase growth methods such as
In the temperature range of ~500°C, the oxygen concentration in the hydrogen atmosphere is not allowed to exceed 0.01% to avoid the risk of explosion. By adding oxygen within this permissible oxygen concentration, the hole concentration that can be obtained is at a limit of 1015 cm-3, and the amount added is more than two orders of magnitude insufficient for producing a practical optical device.

[0008]

SUMMARY OF THE INVENTION The present invention was proposed in order to improve the above-mentioned drawbacks, and its purpose is to improve ZnS -x (0<x<1) Our objective is to develop technology for controlling the conductivity type of mixed crystal semiconductors, especially for making them p-type. Furthermore, by using oxygen gas with a precisely controlled flow rate in the vapor phase growth of the manufacturing method, we are able to improve the controllability and reproducibility of the amount of oxygen added, and at the same time, the oxygen concentration ( 10%) safely.

[0009]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a p-type II film characterized in that it is composed of ZnSx Se1-x (0<x<1) containing oxygen as an acceptor dopant. -The gist of the invention is a group VI mixed crystal semiconductor. Furthermore, the present invention provides ZnSx Se1-x (0≦x
The gist of the invention is a method for producing a p-type II-VI group mixed crystal semiconductor, which is characterized in that crystal growth is performed in an inert gas atmosphere during vapor phase growth in which oxygen is added to ≦1). . Further, the present invention provides a lower cladding layer formed on a substrate of a first conductivity type and made of at least a first conductivity type ZnSx Se1-x, and a lower cladding layer made of at least a first conductivity type ZnSx Se1-x formed on the lower cladding layer. a second active layer formed on the first active layer and made of ZnSx Se1-x of a second conductivity type different from the first conductivity type; an upper cladding layer formed on top of the second conductivity type ZnSx Se1-x, and the optical output is obtained from the junction of the first and second active layers, and the value of x of the cladding layer is equal to the active layer. Among the first conductivity type or second conductivity type regions, which is larger than the value of x of the layer and further corresponds to either p type or n type, the p type region is p type II-VI according to claim 1. The gist of the invention is a light emitting device characterized by being a group mixed crystal semiconductor.

0010

[Function] ■According to the present invention, p-type conduction ZnSx Se1-x containing oxygen is used as an acceptor dopant.
(0<x<1) By obtaining a mixed crystal semiconductor, the hole concentration (P) can be reduced to a practical level in semiconductors without generating deep defect levels, which was a big problem with conventional oxygen-doped ZnSe and ZnS crystals. Area required to realize laser (LD) (P≧
It can be increased up to 1×10 16 cm −3 ). ■Already developed epitaxial growth technology (MOV)
PE method, MBE method, etc.) is applied to create a multilayer Z with different compositions x.
nSx Se1-x crystal films (0<x<1) and superlattice crystal films composed of them can be used as practical devices.
Type conductivity can be performed. ■Already developed n-type mixed crystal ZnSx Se1-x (0≦x<
Through continuous crystal film growth with 1), it is also possible to realize minority carrier injection type light emitting devices (LEDs) with heterostructures made of mixed crystals that effectively confine light and carriers in the active region, and LDs that can operate at room temperature. can. ■The present invention uses only pure oxygen gas as the raw material for oxygen addition in vapor phase growth, typified by MOVPE, and also uses no hydrogen gas, which is used in normal vapor phase growth, to avoid the risk of explosion. Instead of using He, Ar, N2 raw materials
By diluting with an inert gas such as
) can be safely added to MB.
For oxygen-doped p-type ZnSe thin films using the E method, a carrier concentration of ~1016 cm-3 was the limit, but according to the present invention, it has become possible to grow a p-type film with a carrier concentration of ~1017 cm-3 with good reproducibility. Ta. This allows the pn junction, which is the basic structure of blue light emitting devices (LDs, LEDs), to
It has the ability to be mass-produced safely using Group VI semiconductors.

[0011]

[Example] Next, an example of the present invention will be described. Note that the embodiments are merely illustrative, and it goes without saying that various changes and improvements can be made without departing from the spirit of the present invention.

(Example 1) First, ZnSx Se1-x
The results of obtaining p-type conductivity by ion implantation of oxygen atoms into a (0<x<1) mixed crystal semiconductor and subsequent thermal recovery annealing will be described. The mixed crystal semiconductor ZnSx Se1-x (0<x<1) used in this experiment was formed on a GaAs substrate by MOVPE (metal organic vapor phase epitaxy). However, the MOVPE device is the same device as the device (FIG. 2) used in Example 2, which will be described later. The above mixed crystal semiconductor film is formed to a thickness of ~2 μm on a semi-insulating (100) GaAs substrate under non-doped conditions, and then oxygen ion acceleration energy (Ea) is implanted in the range of 180 to 300 KeV. , 450~5 in N2 gas atmosphere
Annealing was performed at a temperature of 20° C., and the properties of oxygen atoms as acceptors in the mixed crystal semiconductor were investigated by photoluminescence and Hall measurements at low temperatures (4.2 K).

In this experiment, the mixed crystal composition x was obtained between 0<x<1, but as a typical example, the mixed crystal composition x=0.03,
The cases of 0.22, 0.52 and 0.72 are shown in FIG. In this experiment, oxygen atoms (0+) are accelerated with an energy of 2
After implantation at 40 KeV and a dose (φ) of 8×10 13 cm −2 , thermal annealing was performed at 500° C. for 2 minutes, and then measurements were taken at 4.2 K. In Figure 1, the spectrum (
a) corresponds to x=0.03, (b) corresponds to x=0.22, (c) corresponds to x=0.52, and (d) corresponds to x=0.72. or,
For reference, the figure shows a comparison with the above-mentioned ion implantation and annealing spectrum (e) of the ZnSe crystal corresponding to x=0.

From FIG. 1, the characteristics of the different spectra of the four compositions x are a small peak near the edge of the band gap (indicated by symbol I in the figure) and a clear donor peak on the longer wavelength side. The acceptor-paired emission peak (DA in the figure) is detected. In addition, the emission peak I near the edge (considered to be excitons bound by donor impurities) and the wavelength position of the emission versus DA become shorter as the composition x increases, reflecting the increase in band gap energy (Eg). It can be seen that there is a shift towards the wavelength side. Also, spectra (a), (b
), (c), (d) and the results of ZnSe used as reference (e)
A comparison between the two shows that almost no emission band is formed due to deep defect levels in a long wavelength region of 500 nm or more. From the wavelength positions of the emission peak (I) near the edges of the spectrum (a) to (d) of the mixed crystal semiconductor and the main peak of DA emission, the position of the energy level of the oxygen acceptor is such that the mixed crystal composition x is 0<x< 85-110 in 0.7
It is in the range of meV (value from the top of the valence band).

Next, the results of electrical conduction (type) characteristics obtained by Hall measurement will be explained. The composition of the mixed crystal semiconductor used in this experiment was a mixed crystal film with a composition between x = 0.03 and x = 0.7, and in order to enable hole measurement, oxygen ions (O+) were implanted with an acceleration energy of 300K
It was carried out using two stages of eV and 180 KeV. Further, the total ion dose (φ) was set to 1×10 14 cm −2 . In ion implantation, by implanting ions with different acceleration energies in multiple stages, the implanted layer can be thickened and the dose can be made uniform, so that conduction characteristics can be detected by hole measurement. In addition, in this experiment, the annealing after ion implantation was 48
This was carried out at 0°C for 3 minutes. The electrode required for hole measurement is A
A u (or Au-Sb) electrode was used.

From this experiment, it was found that the p-type conductive layer was formed in the ion implantation layer (in a region of 0.6 μm from the surface) in a mixed crystal semiconductor with x=0.03 to 0.7. In addition, the hole concentration (P) is 5×1016 to 1×1017 cm−3 for x=0.03 to 0.3, and the hole mobility (μ) is 60 to 80 cm2/V.・It was S. In addition, for a mixed crystal with a composition x of 0.3 to 0.7, P=0.1 to
1×1016cm-3, μ≒70~50cm2/V・
The value of S is shown. The activation rate of oxygen atoms as acceptors changes depending on the composition (x) of the mixed crystal semiconductor, but what is noteworthy is that when the composition x is selected around 0.07, the activation rate of oxygen atoms as acceptors changes. It is particularly excellent in that the hole concentration (P) reaches 1×10 17 cm −3 and the formation of complex defects that become deep emission centers detected in photoluminescence spectra is completely suppressed. This result shows that the above composition x is Ga used in this experiment.
This is thought to be due to lattice matching with the As substrate. The above effect can also be confirmed in an experiment of growth doping of oxygen into a mixed crystal semiconductor, which will be explained in the following examples.

(Example 2) In the next example, ZnSx Se was manufactured by MOVPE using an inert gas as a carrier.
1-x (0≦x≦1) An example of growth doping in which oxygen of a crystal film is added as an acceptor is shown. In this example, ZnSx is used as the II-VI group mixed crystal semiconductor.
Se1-x (x=0.07), as the substrate crystal (10
0) GaAs, raw material dilution and growth atmosphere gas: Ar
The case where oxygen is added by the MOVPE method will be explained using.

FIG. 2 shows the MOVPE used in this example.
An outline of the apparatus (organic metal vapor phase growth apparatus) is shown. In the figure, 1 is a reactor, 2 is a substrate, 3 is a high-frequency coil, 4 is a substrate holder, 5 is an oxygen cylinder, 7 is a hydrogen sulfide cylinder, and 6
, 10, 11, 13, 14, and 16 are gas flow controllers, 8 is an exhaust boat, 9 is diethyl zinc, 12 is a hydrogen selenide cylinder, and 15 is an inert gas introduction line.

In this example, ZnS0.07Se0.
Diethylzinc {(
C2 H5 )2 Zn: hereinafter abbreviated as DEZ}, hydrogen sulfide (H2 S), and hydrogen selenide (H2 Se)
was used. These raw materials are stored in a bubbler container 9 and cylinders 7 and 12, respectively.

The flow rate of the Ar gas supplied from the introduction line 15 is controlled by the flow rate controller 13, and is sent to the DEZ bubbler container 9 to carry DEZ vapor out of the bubbler. DEZ is diluted by Ar gas sent from the flow controller 14 and introduced into the reactor 1. Hydrogen sulfide and hydrogen selenide are each diluted with Ar gas and supplied to the reactor 1.

Oxygen, which is a dopant, is supplied to the reactor 1 using oxygen gas stored in a cylinder 5 as a raw material, with its flow rate controlled by a flow rate controller 6. These matrix raw materials are mixed directly above the GaAs substrate 2 placed on the substrate holder 4 heated by the high frequency coil 3, and an oxygen-doped mixed crystal semiconductor ZnS0.07Se0.93 crystal is formed on the substrate. Examples of film growth conditions are shown below. Growth temperature 230℃~500℃ Reactor pressure
1 Torr to 760 Torr film growth rate
2 to 5 μm/h Oxygen flow rate 0.1 to 10 cc/min Within the above growth conditions, a stable p-type conductive film (positive Pore concentration P = 5 x 1015 cm-3 ~ 5 x 101
6cm-3, hole mobility μ=20-90cm2/V・
S) A crystalline film can grow.

[0022] Furthermore, hydrogen sulfide (H2 S
) by controlling the flow rate of ZnSx with various compositions x.
Se1-x (0<x<1) mixed crystal is grown under the condition of adding oxygen, P=1~80×1015 cm−3, μ=10
It was confirmed that a p-type crystal film of ~95 cm 2 /V·S could be formed. As described above, oxygen-doped p-type ZnSx Se by MOVPE method
Although the experimental results for a single-layer crystal film of 1-x (0<x<1) have been described, it is also possible to use other vapor phase growth methods (CVD method, etc.) as a growth method.

Furthermore, as a method for supplying the acceptor element, oxygen (O), although oxygen gas (O2) was used here, it is also possible to use other oxygen compounds (for example, ZnO, etc.). Furthermore, in the above embodiment, GaA
Although an s-crystal is used as the substrate, it goes without saying that a mixed crystal substrate such as InGaAs, Ge, Si, etc. may be used instead.

In the next example, molecular beam epitaxy (M
Oxygen-doped p-type ZnSx Se1-x by BE)
(0<x<1) will be explained using a GaAs substrate.
It goes without saying that similar effects can be obtained with other materials (GaAs, Si, Ge, etc.).

(Example 3) Figure 3 shows the MB used in this example.
An outline of the E device is shown. In the figure, 25 is an MBE chamber, 26 is a substrate holder, 27 is a substrate, 28 to 32 are Knudsen cells, 28 is metal Se, 29 is Zn, 30
31 is charged with ZnS, 31 is charged with ZnO, and 32 is charged with Ga. Zn, Se and ZnS (or S), which are the raw materials for growing ZnSx Se1-x (0<x<1), are
It is stored in Knudsen cells (hereinafter referred to as K-cells) indicated by 28, 29, and 20 in the figure, and is supplied as a molecular beam by controlling the heating of the K-cells during growth. Oxygen, which is a p-type dopant, is supplied as a high-purity ZnO compound from a K-cell indicated by 31 in the figure. The molecular beam supplied from each K-cell is made of GaAs heated by a heater.
Oxygen-added ZnSx Se1-x on the substrate (27 in the figure)
(0<x<1) A film is formed.

Oxygen-doped ZnSx Se1- was grown using the above growth apparatus and within the following growth conditions.
It became possible to grow a x (0<x<1) film. Substrate temperature: 200-400°C Growth rate: 3 μm/h or less K-cell temperature: K1 (Zn) → 200-350°C K2 (
Se) → 150 to 300°C K3 (ZnS) → 550 to 700°C K4 (ZnO) → 850 to 980°C Within the above growth conditions, p-type conduction ZnSx with a composition x of 0.03 to 0.7 Se1-x was formed. In addition, p-type conduction characteristics are determined by ordinary Hall measurement (Au electrode).
When the composition x is in the range of 0.03 to 0.7, hole concentration (P) = 8 × 1016 to 1 × 1015 cm,
It was found that the mobility (μ) was 100 to 25 cm 2 /V·S. In this growth, when x is 0.5 or more, the crystal quality deteriorates and doping control becomes difficult. However, by improving the growth and doping conditions, p-type mixed crystals can be formed even when x is 0.5 or more. The condition is found to exist. In addition, under the condition that the composition x is set near a value that matches the lattice constant of the GaAs substrate (x = 0.06),
In the case of x=0 where lattice mismatch occurs (ZnSe) and
It is possible to form a p-type mixed crystal film of extremely high quality compared to a mixed crystal film where x is 0.1 or more. For example, even when doped with oxygen at a high concentration (≧1×10 18 cm −3 ), deep defect levels as in ZnSe and ZnS do not occur. P-type mixed crystal semiconductor ZnSx Se of the present invention
By combining the compositions of 1-x (0<x<1),
The following examples will explain that an effective optical confinement layer (cladding layer: x is large) and a photoactive layer (x is small) can be formed in semiconductor lasers and the like, which have not conventionally been realized using this crystal system.

(Example 4) In this example, p-type ZnSx Se1-x (
0<x<1) and the already developed n-type ZnSx S
The characteristics of a pn junction type blue light emitting device with an optical confinement structure formed by continuous growth of an e1-x (0<x<1) film will be described. Figure 4 shows an example of the structure of a light emitting device fabricated by MBE growth.
Shown below. Although this example structure uses an n-type substrate, it goes without saying that a structure in which a p-type substrate is used and the conductivity types of each layer are reversed is also possible.

The basic feature of the present light emitting device is that the mixed crystal composition x
FIG. 4 shows an example of an element structure that satisfies the above conditions by having a structure sandwiched between a photoactive layer with a small x and upper and lower cladding layers with a larger x. In FIG. 4, 41 is an n+ -GaAs substrate, 42 is an n+ type ZnSx Se
1-x (x=0.1), 43 is n-type ZnSx Se1-
x (x=0.07), 44 is p-type ZnSx Se1-
x (x=0.07), 45 is p-type ZnSx Se1-
x (x=0.2), 46 and 47 indicate electrodes. To explain its structure in more detail, n+ type ZnSx Se1 is doped with Ga on an n+ type GaAs substrate 41.
-x (x=0.1) 42 with a thickness of 2 μm, and on top of that, n-type ZnSx Se1- is also doped with Ga.
x (x=0.07) 43 with a thickness of 0.5 μm, and further oxygen-doped p-type ZnSx Se1-x (x=0.0
7) Grow 44 to a thickness of 0.6 μm and use oxygen-doped p-type ZnSx Se1-x (x=0
．． 2) 45 was formed with a thickness of 1 μm. In this device structure, the photoactive layer consists of 43 and 44 layers including the pn junction surface, and the 42nd and 45th layers are optical confinement layers having a larger band gap energy (lower refractive index) than the active layer portions 43 and 44. It has become. Au- on the lower GaAs side electrode.
In alloy, upper p-type ZnSx Se1-x (x=0.
For 2), an Au electrode was formed to fabricate a diode.

FIG. 5 shows the IV characteristics of the mixed crystal light emitting diode of the present invention at room temperature. In Figure 5, the vertical axis is current density (A/cm2) on a logarithmic scale, the horizontal axis is forward bias,
FIG. 6 also shows an IV trace on a linear scale.

From FIG. 5, the n value (exponential factor of the diode) of this diode shows a value around 1.7. The rising voltage under forward bias is ~0.7V, about 2-3V (
forward direction), blue luminescence that can be observed with the naked eye is obtained.

FIG. 6 shows a forward bias of 3 V and a current density of ~10
The room temperature emission spectrum (A) at A/cm2 is
It is shown in comparison with the emission spectrum (B) of a Se diode. ZnSe pn with emission center wavelength ~465 nm
Compared to a junction diode, the light-emitting diode prepared according to the present invention (shown in FIG. 4) has a maximum peak (453 nm) about 12 nm shorter in wavelength, reflecting the increase in the bandgap energy of the light-emitting layer. Moreover, it can be seen that the spectrum is also sharp. Even in terms of luminescence intensity,
When compared under similar current conditions (~10A/cm2),
The mixed crystal diode of the present invention is about 1.5 times more expensive. This is because the photoactive layer has a structure in which the upper and lower sides are sandwiched between cladding layers having a large composition x. Another feature of this mixed crystal diode is that almost no light emission due to deep defect levels is observed on the long wavelength side. This effect is
Not only is it advantageous to increase the purity of blue color, but it is also an important factor when performing laser operation.

As mentioned above, ZnS doped with oxygen
The characteristics of the p-type control of x Se1-x (0<x<1) are:
One of the characteristics is that the generation of complex defects, which cause light emission in the yellow and red long wavelength bands, can be suppressed, and it can be seen that the spectrum of the present invention shown in FIG. 5 strongly reflects this effect.

[0033]

As described above, according to the present invention, in the II-VI group compound semiconductor mixed crystal ZnSx Se1-x (0<x<1) having an emission wavelength from the visible region to the near-ultraviolet region, By adding oxygen, it is possible to make it p-type at a practical device level, and it is also possible to realize a single (or double) heterostructure blue light emitting diode that effectively confines carriers and light, which are the basic structure of an LD, in the active layer. . Furthermore, according to the present invention, an oxygen-doped p-type ZnSx Se1-x thin film can be grown safely and at a high growth rate on a large-area substrate in an inert gas (Ar) atmosphere, making it possible to mass-produce p-n junction blue light-emitting devices. It becomes possible. By applying the present invention to ternary and quaternary mixed crystal systems (Znx Cd1-x Sy Se1-y), it is also effective in the development of pn heterojunctions for blue laser diodes.

[Brief explanation of drawings]

FIG. 1 shows an example of a photoluminescence (PL) spectrum of ZnSxSe1-x in which oxygen was ion-implanted and thermally annealed in the present invention.

FIG. 2 shows a configuration example of a MOVPE device using the present invention.

FIG. 3 schematically shows an MBE apparatus using the present invention.

FIG. 4 shows the structure of a light emitting device of the present invention.

FIG. 5 shows the IV characteristic of the light emitting device of the present invention on a logarithmic scale.

FIG. 6 shows an example of the room temperature emission spectrum of the light emitting device of the present invention.

[Explanation of symbols]

1 Reaction furnace 2 Substrate 3 High frequency coil 4 Substrate holder 5 Oxygen cylinder 6, 10, 11, 13, 14, 16 Gas flow controller 7 Hydrogen sulfide cylinder 8 Exhaust boat 9 Diethyl zinc 12 Hydrogen selenide cylinder 15 Impurity gas introduction line 25 MBE Chamber 26 Substrate holder 27 Substrate 28 Knud sensor cell 29 charged with metal Se Knud sensor cell 30 charged with Zn
Knud Sensel 31 charging ZnS
Knud Sensel 32 charging ZnO
Knud Sensel 41 n+ charging Ga
-GaAs substrate 42 n+ -ZnSx Se1-x (x=0.1
)43 n-ZnSx Se1-x (x=0.07
)44 p-ZnSx Se1-x (x=0.07
)45 p-ZnSx Se1-x (x=0.2)
46 Lower electrode 47 Upper electrode

Claims (3)

[Claims] 1. A p-type II-VI group mixed crystal semiconductor comprising ZnSx Se1-x (0<x<1) containing oxygen as an acceptor dopant. [Claim 2] Zn having a zincblende crystal structure.
A method for producing a p-type II-VI group mixed crystal semiconductor, characterized in that crystal growth is performed in an inert gas atmosphere in vapor phase growth in which oxygen is added to Sx Se1-x (0≦x≦1). 3. A lower cladding layer made of at least a first conductivity type ZnSx Se1-x formed on a substrate of a first conductivity type, and a first conductivity type lower cladding layer formed on the lower cladding layer.
a first active layer made of a conductivity type ZnSx Se1-x; and a second active layer made of a second conductivity type ZnSx Se1-x different from the first conductivity type formed on the first active layer.
an upper cladding layer made of ZnSx Se1-x of a second conductivity type formed on the second active layer, and the optical output is obtained from the junction of the first and second active layers. and the value of x of the cladding layer is larger than the value of x of the active layer, and the p-type region of the first conductivity type or second conductivity type region corresponding to either p-type or n-type is is a p-type II-VI group mixed crystal semiconductor according to claim 1.