JP2001144328A - Light-emitting device and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device which is high in luminous performance of plasma emission or the like, and emission intensity and a method of manufacturing the same. SOLUTION: A ZnO thin film, having a 'positive surface' or a ZnO thin film, whose surface is piezoelectrically positive, is formed on a substrate 2 such as a C-plane sapphire substrate, a z-plane quartz substrate or the like. This thin film has an emission intensity higher than a ZnO thin film having its upper surface turned into a 'negative surface'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light emitting device and a method for manufacturing the same, and more particularly, to a light emitting device having a light emitting layer made of a piezoelectric material and a method for manufacturing the same.

[0002]

2. Description of the Related Art Thin-film piezoelectric materials are widely applied to vibrators and driving elements such as piezoelectric resonators and piezoelectric actuators. In recent years, piezoelectric thin films have attracted attention as optical elements. For example, JP-A-7-262801 discloses that
A light emitting element having a ZnO film formed on a sapphire substrate and emitting ultraviolet light by excitons is disclosed. Further, Japanese Patent Application Laid-Open No. Hei 10-256673 discloses a light emitting element that emits ultraviolet light by laser oscillation.

[0003]

However, the physical properties of the piezoelectric film are largely unknown, and the physical properties of the piezoelectric film particularly suitable for a light emitting element and the method of forming the piezoelectric film have not yet been sufficiently studied. For this reason, a light emitting element having a piezoelectric film with high luminous efficiency has not been realized.

The present invention has been made in view of the above technical background, and an object of the present invention is to provide a light emitting device having high luminous efficiency and high luminous intensity, and a method of manufacturing the same. It is in.

[0005]

According to a first aspect of the present invention, there is provided a light emitting device comprising a substrate and a first surface which is held on the substrate and has either a + surface or a-surface on an upper surface and functions as a light emitting layer. And a piezoelectric film.

According to a second aspect of the present invention, in the light emitting element according to the first aspect, the substrate is a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, or a rotating Y-plate sapphire. A substrate selected from a substrate, a double rotation sapphire substrate, a rotating Y-plate quartz substrate, a Z-plane quartz substrate, a LiTaO ₃ substrate having a -Z surface, a LiNbO ₃ substrate having a -Z surface, and a piezoelectric substrate having a-surface. The first piezoelectric film has a positive surface.

According to a third aspect of the present invention, in the light emitting device according to the first aspect, the substrate is a rotating Y plate LiN.
a LiNbO ₃ substrate having a + Z plane side of bO ₃ , a LiTaO ₃ substrate having a + Z plane side of a rotating Y plate LiTaO ₃ , +
LiNbO ₃ substrate with Z plane, LiT with + Z plane
The substrate is selected from an aO ₃ substrate, a glass plate, a Si substrate, a metal substrate, a piezoelectric substrate having a positive surface, and a substrate having a metal film on its surface, and the first piezoelectric film has a negative surface.

According to a fourth aspect of the present invention, in the light emitting device according to the second or third aspect, the first piezoelectric film is
It contains any material selected from ZnO, AlN, and CdS.

[0009] The light emitting device according to the fifth aspect is characterized in that:
5. The light-emitting device according to any one of the items 4, further comprising a second piezoelectric film, wherein the first piezoelectric film and the second piezoelectric film have different conductivity types.

A light emitting device according to a sixth aspect of the present invention has a plurality of stripe-shaped metal films formed on the substrate in the light emitting device according to the second aspect, and the light emitting device covers the metal film. One piezoelectric film is provided, and the first piezoelectric film on the metal film has a negative surface.

[0011] A method for manufacturing a light emitting device according to claim 7 is provided.
The method includes a step of preparing a substrate, and a step of forming a first piezoelectric film having either a + surface or a − surface on the upper surface on the substrate based on characteristics of the substrate.

[0012] The method for manufacturing a light emitting device according to claim 8 is characterized in that:
8. The method according to claim 7, wherein the substrate is a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, a rotating Y-plate sapphire substrate, a double rotation sapphire substrate, or a rotating Y-plate. Quartz substrate, Z-plane quartz substrate, LiTa having -Z plane
O ₃ substrate is a substrate selected from LiNbO ₃ substrate having a -Z face, the first piezoelectric film are those having a + plane.

[0013] According to a ninth aspect of the present invention, there is provided a method for manufacturing a light emitting device.
The substrate in the method of manufacturing the light emitting device according to claim 7, LiNb with + Z side of the rotation Y plate LiNbO ₃
L having an O ₃ substrate, a rotating Y plate LiTaO ₃ having a + Z plane side
iTaO ₃ substrate, LiNbO ₃ substrate having + Z plane, +
A substrate selected from a LiTaO ₃ substrate having a Z plane, a piezoelectric substrate having a + plane, a glass plate, a Si substrate, a metal substrate, and a substrate having a metal film on its surface, wherein the first piezoelectric film has a − plane Things.

According to a tenth aspect of the present invention, in the method for manufacturing a light emitting element according to the eighth or ninth aspect, the first piezoelectric film is made of any material selected from ZnO, AlN, and CdS. Is included.

According to an eleventh aspect of the present invention, there is provided a method for manufacturing a light emitting device according to any one of the seventh to tenth aspects, wherein the first piezoelectric film and the conductive film are formed on the first piezoelectric film. The method further includes a step of forming a second piezoelectric film of a different type.

[0016]

The present invention is based on the knowledge obtained by focusing on the relationship between the physical characteristics of a piezoelectric film used for a light emitting element and its orientation, the type of substrate and the method of orientation of the piezoelectric film suitable for the substrate. . That is, by appropriately selecting the orientation direction of the piezoelectric film according to the type of the substrate, the crystallinity of the piezoelectric film is improved, and as a result, a light emitting element having good characteristics is realized.

However, conventionally, no consideration has been given to the relationship between the physical characteristics of the piezoelectric film and its orientation, and the relationship between the type of substrate and the orientation direction of the piezoelectric film suitable for it. In the present invention, the point of interest itself is unique.

In this specification, the positive and negative planes in the orientation direction of the piezoelectric film relate to the sign of the charge generated on the main surface of the thin film. The + surface is a surface on which a positive charge is generated in the piezoelectric film due to the tension. In the ZnO thin film, the AlN thin film, and the CdS thin film, they are considered to correspond to the Zn surface, the Al surface, and the Cd surface, respectively. The-surface is a surface on which a negative charge is generated in the piezoelectric film due to the tension, and the ZnO thin film, AlN
It is considered to correspond to the O-plane, N-plane, and S-plane of the thin film and the CdS thin film.

Specifically, a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, a rotating Y-plate sapphire substrate, a double rotation sapphire substrate, a rotating Y-plate quartz substrate, a Z-plane quartz substrate, -Z
LiTaO ₃ substrate with surface, LiNb with -Z surface
O ₃ when forming the piezoelectric film on the surface of the substrate, the surface of the piezoelectric film + surface (the side in contact with the substrate - the surface) and a ZnO film is formed on the substrate so as to. Here, “Li having −Z plane”
“TaO ₃ ” is a surface on which a negative surface charge is generated when tension is generated on a surface in the Z-axis direction (Z-plane). Also, Li
The TaO ₃ substrate does not need to be polarized.

Also, a rotating Y plate LiNbO₃+ Z side
LiNbO having₃Substrate, rotating Y-plate LiTaO₃+ Z
LiTaO with surface side₃Substrate, LiN with + Z plane
bO ₃LiTaO with substrate, + Z plane₃Substrate, + side
Having piezoelectric substrate, glass plate, Si substrate, metal substrate, metal
When forming a piezoelectric film on the surface of a substrate having a film on the surface,
The surface of the piezoelectric film will be negative (the side in contact with the substrate will be positive)
Thus, a ZnO film is formed on the substrate.

The piezoelectric film formed on such a substrate has a Z
It is preferably made of a material selected from nO, AlN, and CdS. In particular, for devices that emit ultraviolet light, Zn
It is preferable to use a piezoelectric film made of O.

Whether the piezoelectric film formed on the substrate has a positive surface or a negative surface is determined by a method of forming the piezoelectric film, forming conditions, surface treatment of the substrate, and the like. For example, when an ECR apparatus such as an ECR plasma CVD apparatus or an ECR sputtering apparatus is used, the power of the microwave is increased (for example, 300 W or more) or the heating temperature of the substrate is increased (for example, 50
(0 ° C. or more), the piezoelectric film tends to have a positive surface. In particular, a piezoelectric film formed on a substrate heated at a temperature of 1000 ° C. or higher for several hours in an atmosphere such as N ₂ , O ₂ , H ₂ O, or the like has a favorable + plane.

Further, the polarity (+ plane or − plane) can be controlled by adjusting the substrate bias voltage. In the case of a sputtering apparatus, the gas composition during film formation, the heating temperature of the substrate,
By appropriately adjusting the bias voltage or the like applied to the substrate, a positive surface piezoelectric film or a negative surface piezoelectric film can be obtained. In particular, the polarity can be effectively controlled by applying a bias voltage of -500 V to +500 V.

According to the present invention, by forming a piezoelectric film having a + surface or a-surface according to the type of the substrate, a light emitting device having a high light emission intensity can be obtained.

[0025]

(First Embodiment) FIG. 1 schematically shows a cross section of a light emitting device 1 according to a first embodiment of the present invention. The light emitting device 1 has a substrate 2 and a ZnO thin film 3 formed thereon. As the substrate 2, a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, a rotating Y-plate sapphire substrate, a double rotation sapphire substrate, a rotating Y-plate quartz substrate, a Z-plane quartz substrate, a -Z surface A LiTaO ₃ substrate having:
When a LiNbO ₃ substrate having a −Z plane and a piezoelectric substrate having a −plane are used, the ZnO thin film 3 has a + Z plane.

On the other hand, a rotating Y plate LiNbO₃+ Z side
LiNbO having₃Substrate, rotating Y-plate LiTaO₃+ Z
LiTaO with surface side₃Substrate, LiN with + Z plane
bO ₃LiTaO with substrate, + Z plane₃Substrate, + side
Having piezoelectric substrate, glass plate, Si substrate, metal substrate, metal
When a substrate having a film on its surface is used as the substrate 2
The ZnO thin film 3 has a -Z plane.

The light emitting element 1 emits light by the combination of excitons or electrons and holes. As shown in FIG. 1, by irradiating the ZnO thin film 3 with a He—Cd laser, the light emitting device 1 emits light having a wavelength of 370 nm corresponding to the band gap of ZnO at room temperature based on photoluminescence. .

It has been confirmed from various experiments that a piezoelectric film having excellent crystallinity can be obtained by the above combination. In the following experiments, a C-plane sapphire substrate and a Z-plane quartz substrate were used as substrates, and various piezoelectric films were formed by changing the film forming conditions and the surface conditions of the substrates.
The orientation direction of the nO thin film was confirmed with a dielectric microscope. Specifically, three samples were prepared using an ECR sputtering apparatus under the following conditions.

FIGS. 2 to 4 are photographs of various piezoelectric films manufactured as described above, taken with a dielectric microscope. FIG. 2 shows a film produced under the condition 1. In the photograph of FIG. 2, a dark portion is a region where a positive charge is generated by tension, and a light portion is a region where a negative charge is generated by tension. It is the area where it occurs. Therefore, both regions are mixed as a whole, and are neither a + plane nor a − plane.

FIG. 3 shows a film produced according to condition 2. The dielectric micrograph shown in FIG. 3 is uniformly dark in color as a whole, indicating a uniform + plane.

FIG. 4 shows a film manufactured under the condition 3. The dielectric micrograph of FIG. 4 is uniformly light in color throughout, indicating a uniform -plane. As described above, by controlling the conditions, a piezoelectric film having a negative surface or a positive surface and a piezoelectric film having neither a negative surface nor a positive surface can be selectively formed.

Even under conditions other than conditions 2 and 3, a film having a negative surface is easily formed by applying a negative bias voltage to the substrate, and by applying a positive bias voltage to the substrate, It was found that a film having a + plane was formed.

After confirming the orientation direction of the ZnO film thus manufactured, a light emitting device having the manufactured ZnO thin film was manufactured, and a photoluminescence emission measurement test was performed by irradiating a He-Cd laser. FIG. 5 shows the result of measuring the light emission intensity of a ZnO thin film having a + plane formed on a C-plane sapphire substrate in a region of 350 to 400 nm, and FIG. 6 shows the + plane formed on a Z-plane quartz substrate. 3 shows the results of measuring the emission intensity of a ZnO thin film having a thickness of 360 to 390 nm. FIG. 5 shows 367.8 n
6 shows a sharp peak considered to correspond to an exciton at a wavelength of m, and FIG. 6 also shows a similar peak at 368 nm.

FIG. 7 shows the luminous intensity of a ZnO thin film having a + face and a ZnO thin film having a − face formed on a C-plane sapphire substrate in comparison. As is clear from the figure,
The ZnO thin film having a + plane has a light emission intensity about 5 times as large as that of a ZnO thin film having a − plane, and has a small half width. This indicates that the ZnO thin film having the + plane formed on the C-plane sapphire substrate shows good characteristics.

FIG. 8 is a graph showing the relationship between C and C using a Zn metal target.
2 shows X-ray diffraction intensities of ZnO thin films formed under various conditions on a planar sapphire substrate. In FIG. 8, the horizontal axis is Z
The vertical axis indicates the partial pressure ratio between Ar and O ₂ , which are atmosphere gases during the formation of the nO thin film, and the vertical axis indicates the X-ray diffraction intensity (relative value) of the ZnO thin film.
Is shown. Also, the data shows that the substrate heating temperature is 200 ~
The measurement is performed by changing the temperature between 600 ° C. In FIG. 8, in a region where the X-ray diffraction intensity is 4 × 10 ⁴ [au] or more, the ZnO thin film has a + plane, and the diffraction intensity is 9 × 10 ³ [au]. In the following areas, the + plane area and-
The area of the surface is mixed. In addition, a ZnO thin film having a + plane and a ZnO thin film having a − plane are formed in the intermediate region, and the film formation cannot be reliably controlled. Note that a ZnO thin film formed on a Z-plane quartz substrate also shows the same tendency.

FIG. 9 shows the result of similarly forming a ZnO thin film on a -Z-plane LiNbO ₃ substrate. in this case,
In a region where the X-ray diffraction intensity is 1.4 × 10 ⁵ [au] or more, the ZnO thin film has a + plane, and the diffraction intensity is 9 × 10 ³ [au] or less. In the area, the area of the + plane and-
The area of the surface is mixed. In addition, a ZnO thin film having a + plane and a ZnO thin film having a − plane are formed in the intermediate region, and the film formation cannot be reliably controlled.

As is apparent from FIGS. 8 and 9, Ar
By changing the partial pressure ratio between O ₂ and O ₂ , the orientation of the ZnO thin film can be controlled, and the partial pressure ratio of Ar / O ₂ becomes 7
Zn having good + plane in the range of 5/25 to 65/35
It can be seen that an O thin film can be formed. Also, C
When a ZnO thin film having a + plane is formed on a plane sapphire substrate, the orientation of the ZnO thin film is improved by heating the substrate to 500 ° C. or higher, and the + Z plane is formed on a + Z plane LiNbO ₃ substrate.
In the case of forming a ZnO thin film having a surface,
It can be seen that heating to 0 ° C. or higher is sufficient.

In the above embodiment, a ZnO thin film has been exemplified as the piezoelectric film. However, a thin film made of AlN and CdS having a positive surface is formed by a C-plane, an R-plane, an m-plane and an a-plane sapphire substrate.
Plate sapphire substrate, double rotation sapphire substrate, rotating Y plate quartz substrate, Z-plane quartz substrate, Z-plane quartz substrate,
LiTaO ₃ substrate having -Z plane, Li having -Z plane
Similarly, a light emitting element having good light emitting characteristics can be obtained by forming it on a NbO ₃ substrate or a piezoelectric substrate having a negative surface.

FIG. 10 is a schematic sectional view of a light emitting device 11 according to the second embodiment of the present invention. Light emitting element 11
Is a C-plane sapphire substrate 12, a plurality of Al films 13 formed thereon in a stripe pattern at regular intervals, and an Al film 1
3 includes a ZnO thin film 14 formed on a C-plane sapphire substrate 12 so as to cover 3. The ZnO thin film 14 is made of the Al film 13
14a located above the C-plane sapphire substrate 12
Including an area 14b located directly above, the areas 14a and 1
4b are alternately arranged along the direction α. Area 1
4a has a negative surface, and the region 14b has a positive surface. Therefore, only the portion where the Al film 13 is provided has a negative surface. Instead of the C-plane sapphire substrate 12, another substrate, such as a rotating Y-plate quartz substrate or a Z-plane quartz substrate, on which a + -plane ZnO thin film is preferably formed may be used.

The C-plane sapphire substrate and the Al film are made of ZnO.
Since there is a difference in the orientation characteristics with respect to the thin film, it is possible to alternately form the − plane region and the + plane region by appropriately selecting the film formation conditions. Also, A
Even if positive and negative bias voltages are respectively applied to the 1 film and the sapphire substrate, a film in which the direction of the C axis is alternately inverted can be obtained.

The light emitting element 11 functions as an SHG element. As shown in FIG. 10, blue light is emitted from the other end surface of the ZnO thin film 14 by causing red light to enter the ZnO thin film 14 from one end surface of the ZnO thin film 14 along the direction α. As described above, according to the present invention, an SHG element having good characteristics can be easily realized.

FIG. 11 shows a light emitting device 2 according to the third embodiment.
1 schematically shows a cross section. The light emitting element 21 includes a C-plane sapphire substrate 22, and an n-type ZnO layer 23, a ZnO active layer 24, and a p-type ZnO layer 25 formed thereon. The upper surface of the n-type ZnO layer 23 is a + surface, and similarly, the ZnO active layer 24 and the p-type ZnO layer 25 also have the + surface as the upper surface. ZnO active layer 24 and p-type Zn
The O layer 25 constitutes a light emitting section 26. Also, n-type Zn
The O layer 23 is doped with a group III element such as Al as an impurity and has a low resistance. Similarly, the p-type ZnO layer 2
5 is also doped with group V elements such as P and As. Electrode 2
7 and 28 are n-type ZnO layer 23 and p-type ZnO layer 2
5, current is injected from the electrodes 27 and 28, and light emission by excitons is caused in the light emitting unit 26.

According to such a structure, n having a + plane
Since the ZnO active layer 24 having the + plane and the p-type ZnO layer 25 are provided on the
The light emitting element 21 having high crystallinity, high luminance and high luminous efficiency can be realized.

In this embodiment, the n-type ZnO layer 23 is provided on the C-plane sapphire substrate 22, but the conductivity type is reversed by replacing the n-type ZnO layer 23 and the p-type ZnO layer 29, and the sapphire A p-type ZnO layer may be provided on the substrate 22 and an n-type ZnO layer may be provided on the ZnO active layer 28.

FIG. 12 schematically shows a light emitting device 31 according to the fourth embodiment, which represents an edge emitting light emitting device such as a laser diode or an edge emitting light emitting diode. The light emitting element 31 includes a sapphire substrate 32, a low resistance ZnO layer 33 provided thereon, and a light emitting section. The sapphire substrate 32 has a C-plane, an R-plane, an m-plane, a
Surface or a rotating Y-plate sapphire surface, and the low-resistance ZnO layer 33 has a + surface as its upper surface. The light emitting section 34 includes a p-type ZnO layer 35, a ZnO active layer 36, an n-type ZO
The nO layer 37 is included, and these layers 36 and 37 are influenced by the orientation direction of the low-resistance ZnO layer 33, and each of them has a + surface on its upper surface.

On the light emitting portion 34, a Si having a slit is provided.
An O ₂ film 38 is provided, and SiO _{2 is}
An upper electrode 39 is provided on the film 38. Further, a part of the light emitting portion 34 is etched so that a part of the low resistance ZnO layer 33 is exposed, and the exposed low resistance ZnO layer 3 is exposed.
A lower electrode 40 is formed on 3.

In the light emitting element 31, when a voltage is applied between the upper electrode 39 and the lower electrode 40, blue to ultraviolet light due to exciton emission is emitted from the end face. Since each of the layers 36 and 37 of the light emitting section 33 has a + plane, a light emitting element having high crystallinity, high luminance, and high luminous efficiency is realized.

[0048]

According to the present invention, according to the type of the substrate,
A piezoelectric film having a + plane or a − plane is selectively provided, and such a piezoelectric film has high crystallinity. Therefore, a light-emitting element with high luminance and high luminous efficiency is realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a photoluminescence characteristic measurement of a light emitting device according to a first embodiment.

FIG. 2 is a view showing a dielectric micrograph of a ZnO thin film in which a + -plane region and a −-plane region are mixed.

FIG. 3 is a view showing a photomicrograph of a dielectric constant of a + ZnO thin film.

FIG. 4 is a view showing a photomicrograph of a dielectric constant of a ZnO thin film.

FIG. 5 is a diagram showing the emission intensity of a ZnO thin film having a + plane formed on a C-plane sapphire substrate.

FIG. 6 shows Zn having a + plane formed on a Z-plane quartz substrate.
It is a figure which shows the light emission intensity of an O thin film.

FIG. 7 is a diagram showing a comparison between the emission intensity of a ZnO thin film having a + plane and a ZnO thin film having a − plane formed on a C-plane sapphire substrate.

FIG. 8 is a diagram showing the X-ray intensity of a ZnO thin film having a + plane formed on a C-plane sapphire substrate.

FIG. 9 is a diagram showing the X-ray intensity of a ZnO thin film having a + plane formed on a −Z plane LiNbO ₃ substrate.

FIG. 10 is a sectional view schematically showing a light emitting device according to a second embodiment of the present invention.

FIG. 11 is a sectional view schematically showing a light emitting device according to a third embodiment of the present invention.

FIG. 12 is a sectional view schematically showing a light emitting device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 light emitting element 2 substrate 3 thin film

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) C09K 11/64 CQF C09K 11/64 CQF H01S 5/323 H01S 5/323 5/327 5/327

Claims (11)

[Claims] 1. A light-emitting element including: a substrate; and a first piezoelectric film held on the substrate and having either a + surface or a − surface on an upper surface and functioning as a light-emitting layer. 2. The substrate includes a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, a rotating Y-plate sapphire substrate, a double rotation sapphire substrate, a rotating Y-plate quartz substrate, and a Z-plane quartz substrate. , −
LiTaO ₃ substrate with Z plane, LiN with -Z plane
The light emitting device according to claim 1, wherein the first piezoelectric film has a + surface, wherein the substrate is a substrate selected from a bO ₃ substrate and a piezoelectric substrate having a-surface. 3. The method according to claim 1, wherein the substrate is a rotating Y-plate LiNbO ₃ +
LiNbO ₃ substrate with Z-plane side, rotating Y-plate LiTaO
A LiTaO ₃ substrate having a _third + Z side, LiNbO ₃ substrate having a + Z face, LiNbO ₃ substrate having a + Z face, the piezoelectric substrate having a + plane, the glass plate, Si substrate, a metal substrate, a metal film on the surface thereof The light emitting device according to claim 1, wherein the first piezoelectric film has a negative surface, which is a substrate selected from substrates. 4. The method according to claim 1, wherein the first piezoelectric film is made of ZnO, AlN,
The light-emitting device according to claim 2, wherein the light-emitting device includes any material selected from CdS. 5. The light emitting device according to claim 1, further comprising a second piezoelectric film, wherein the first piezoelectric film and the second piezoelectric film have different conductivity types. . 6. A semiconductor device comprising: a plurality of stripe-shaped metal films formed on the substrate; and the first piezoelectric film provided so as to cover the metal films. The light emitting device according to claim 2, wherein the one piezoelectric film has a negative surface. 7. A light emitting device comprising: a step of preparing a substrate; and a step of forming a first piezoelectric film having either a + surface or a − surface on the substrate based on characteristics of the substrate. Device manufacturing method. 8. The substrate includes a C-plane sapphire substrate, an R-plane sapphire substrate, an m-plane sapphire substrate, an a-plane sapphire substrate, a rotating Y-plate sapphire substrate, a double rotation sapphire substrate, a rotating Y-plate quartz substrate, and a Z-plane quartz substrate. , −
LiTaO ₃ substrate with Z plane, LiN with -Z plane
bO ₃ substrate and - a substrate selected from a piezoelectric substrate having a surface, wherein the first piezoelectric film and having a + plane, the method of manufacturing the light emitting device according to claim 7. 9. The method according to claim 1, wherein the substrate is a rotating Y-plate LiNbO ₃ +
LiNbO ₃ substrate with Z-plane side, rotating Y-plate LiTaO
₃ , a LiTaO ₃ substrate having a + Z plane side, a LiNbO ₃ substrate having a + Z plane, LiTaO ₃ having a + Z plane, +
Piezoelectric substrate having a surface, a glass plate, a Si substrate, a metal substrate,
The method according to claim 7, wherein the first piezoelectric film is a substrate selected from a substrate having a metal film on a surface thereof, and the first piezoelectric film has a negative surface. 10. The first piezoelectric film is made of ZnO, Al
The method for manufacturing a light emitting device according to claim 8, wherein the method includes any one material selected from N and CdS. 11. The light emission according to claim 7, further comprising a step of forming a second piezoelectric film having a different conductivity type from the first piezoelectric film on the first piezoelectric film. Device manufacturing method.