JPS63239750A - Electron emission element - Google Patents

Abstract

PURPOSE:To aim at promotion for low voltage and improvement in electron emission efficiency, by constituting a peak part an electrode from at least the semiconductorcrystal made by unclear growth and a low work function material. CONSTITUTION:With the single nucleus formed in a nucleation base 2 as the center, a monocrystal of Si or the like is grown up while adding n-type impurities to it, and an n-type semiconductor area 9 is formed up, and furthermore a p-type semiconductor area 10 is formed while adding p-type impurities onto this n-type semiconductor area 9. The p-type semiconductor area 10 has a facet peculier to the monocrystal, on which a low work function material area 11 of CsSi or the like is formed, whereby such an electrode as having a peak part serving as an electron emission part is formed. With this constitution, promotion for low voltage is contrivable as well as improvement in electron emission efficiency is promotable.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to an electron-emitting device, and in particular to an electrode having a pointed head provided on a deposition surface, and an electrode provided on the deposition surface and of the pointed head. The present invention relates to an electron-emitting device having an extraction electrode provided nearby.

[Prior art] Conventionally, hot cathode quasiton emitters have been widely used as electron emission sources, but electron emission using 1.8 electrodes has problems such as large energy loss due to heating and the need for preheating. It had a point.

In order to solve these problems, several cold cathode type electron emitting devices have been proposed, and a field effect type electron emitting device that generates a locally high electric field in the device and emits 7V electrons by field emission. There is an emitting element.

FIG. 14 is a schematic partial cross-sectional view showing an example of the above-mentioned field effect type electron-emitting device.

As shown in FIG. 14, a conical electrode 26 made of Mo (molybdenum) or the like is provided on a substrate 23 made of Si or the like, and an insulating layer 24 such as 5i02 with an opening formed around the upper electrode 26 is formed. An extraction electrode 25 is provided thereon, the end of which is formed near the conical point.

In the electron-emitting device having such a structure, when a voltage is applied between the base 23 and the extraction electrode 25, electrons are emitted from the tip where the electric field strength is strong.

[Problems to be Solved by the Invention] However, the field-effect electron-emitting device described in 1.
Generally, an applied voltage of 100 V or more is required, making it difficult to integrate into an IC, and a lower voltage has been desired.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to provide an electron-emitting device that can lower the voltage and further improve the electron-emitting efficiency.

[Means for Solving the Problems] An electron-emitting device according to the present invention includes an electrode having a pointed head provided on a deposition surface, and a drawer provided on the deposition surface and near the pointed head. An electron-emitting device having an electrode, characterized in that the tip of the electrode is composed of at least a semiconductor crystal produced by nuclear growth and a low work function material.

[Function] The present invention aims at low voltage and improves electron emission efficiency by constructing the tip of the electrode from at least a semiconductor crystal made by nuclear growth and a low work function material. be.

As the semiconductor crystal, a p-type semiconductor crystal and/or an n-type semiconductor crystal can be used. A case will be described in which electrons are emitted using a p-type semiconductor crystal and a low work IA number material of 6 or less.

First, the principle of electron emission operation of the present invention will be explained.

FIG. 4 is an energy band diagram of a metal-semiconductor junction.

FIG. 5 is an energy band diagram of the semiconductor surface in the present invention.

In order to achieve the NEA state in which the vacuum level Evac is at a lower energy level than the conduction band Ec of the P-type semiconductor as shown in Figure 4, it is necessary to add a material that lowers the work function φ to the semiconductor surface. It is necessary to form the As such low work function materials, alkali metals are typical, and in particular, Cs, Cs-0, etc. are used. When the work function φJ of the semiconductor surface is in a low state, furthermore, in the NEA state, electrons injected into the p-type semiconductor are easily emitted, and an electron-emitting device having high electron emission efficiency can be obtained.

Furthermore, by reverse biasing the junction between the p-type semiconductor and the low work function material, as shown in FIG.
The vacuum level Evac is set to an energy level lower than the conduction band Ec of the p-type semiconductor. As a result, it is possible to easily obtain a larger energy difference ΔE than before, and by using a chemically stable low work function material with a relatively large work function φ layer, the vacuum level Evac is reduced to p in the equilibrium state. Even if the energy level is higher than the conduction band Ec of the type semiconductor,
NEA state can be easily obtained.

The present invention aims to reduce the voltage and improve the electron emission efficiency by using such an electron-emitting structure in a structure similar to a field-effect electron-emitting device.

Note that it is also possible to form an electron-emitting device using an n-type semiconductor crystal and a low work function material, for example, as described in Ph1lips J, Reg, 39.59.
-80.1984.

In addition, in the present invention, a dissimilar material is formed on the deposition surface, the nucleation density of which is sufficiently higher than that of the material on this deposition surface, and which is sufficiently small to the extent that only the nuclei grow. If an electrode having a pointed head is formed using a crystal aging method in which a single crystal is grown around a single nucleus, the following effects will occur.

(1) A single nucleus is formed only on the dissimilar material which is the nucleation surface, and no nucleus is formed on the deposition surface which is the non-nucleation surface, so only a single crystal can be formed.

Furthermore, the facets unique to single crystals can be used as the peaks of the electron-emitting portions.

(2) The shape of the electrode with the pointed head is determined by manufacturing conditions such as the deposition surface, the surface of different materials, the material of the electrode, and the deposition conditions, so that it is possible to form an electrode with a desired size, and It is possible to suppress variations in the height.

(3) Since the position of the electrode having the pointed head is determined by the positional accuracy of the surface of different materials, it can be manufactured at a desired position with high precision.

(4) It becomes easy to grow a single crystal even on the surface of an amorphous insulating material, where it has been difficult to grow a single crystal in the past.

(5) Since it can be manufactured using a normal semiconductor manufacturing process, high integration can be achieved with a simple process.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

Regarding the following embodiments, FIG. 1 is a schematic partial sectional view for explaining one embodiment of the electron-emitting device of the present invention.

FIG. 2 is an explanatory diagram of the operation of this embodiment.

As shown in the figure, a nucleation base 2 made of a different material such as Si3N4 is formed on an oxidized substrate 1 made of 5i02 or the like which is an amorphous insulating material constituting the deposition surface. A single crystal of Si or the like is grown around a single nucleus formed in these nucleation bases 2 while adding an n-type impurity to form an n-type semiconductor region 9. Further, on this n-type semiconductor region 9, p
A p-type semiconductor region 1o is formed while adding type impurities. The p-type semiconductor region 10 has a facet peculiar to a single crystal, and by forming about 100 low work function material regions 11 of CsSi ¥ on this, an electrode 13 having a pointed end that becomes an electron emitting region is formed. form. As the low work function material, materials with a φ of about 2.5 eV or less are desirable, such as Li and Na.

K, Rb, Sr, Cs, Ba, Eu, Yb, Fr, etc. can be used. Furthermore, in consideration of stabilizing the low work function material region 11, alkali metal silicides such as CsSi and RbSi may be used. The method for manufacturing the single crystal will be described later.

The n-type semiconductor region 9 of the formed 'electrode 13 is an oxidized base l.
An insulating layer 4 such as 5i02 is formed on the conductive layer 3, connected to the conductive layer 3 provided on the north side, and having an opening centered around the formed electrode 13. Furthermore, a conductive layer 5 connected to the p-type semiconductor region 10 is formed on this insulating layer 4, and an insulating layer 6 is formed thereon. A conductive region 8 connected to a low work function material region 9 is formed on this insulating layer 6 . An insulating layer 7 is formed on the insulating layer 6 other than this conductive region 8.
, and further, an extraction electrode 12 is formed.

In an element having such a configuration, as shown in FIG.
A voltage V2 that makes the p-type semiconductor region 10 at a high potential is applied between the n-type semiconductor region 9 and the p-type semiconductor region 10, and a reverse bias voltage is applied between the p-type semiconductor region IO and the low work function material region 11. Electrons can be emitted from the surface of the low work function material region 11 by applying voltage v1 and further applying a voltage V3 between the p-type semiconductor region lO and the extraction electrode 12 to make the extraction electrode 12 a high potential. This operation will be explained next.

FIG. 3(A) is an energy band diagram in the equilibrium state of this embodiment, and FIG. 3(B) is an energy band diagram in the operation of this embodiment.

As shown in Figure 2, the forward bias voltage V
2. P-type semiconductor region IO and low work function material region 11
When a reverse bias voltage v1 is applied between
As shown in B), the energy band changes, and as described above, the NEA state is reached in which the J vacant level Evac is at a level ΔE lower than the conduction band Ec of the p-type semiconductor region 10.

For this purpose, from the n-type semiconductor region 9 to the p-type semiconductor region 10
The electrons injected into the surface of the low work function material region 11 -
61, and because ΔE is larger than conventional electron emission efficiency can be obtained.

In addition, in order to increase ΔE by reverse bias, Cs with a small work function and (:
, s-0, etc., it is possible to select materials from a wide range such as alkali metals and alkaline earth metals as described above, and more stable materials can be used.

Furthermore, in this embodiment, since a positive voltage is further applied to the extraction electrode 12, the work function is lowered due to the Shigotki effect, and an even larger amount of electron emission can be obtained.

In the above embodiments, the P-type semiconductor region and the n-type semiconductor region are grown using a single crystal growth method, that is, on a deposition surface, the nucleation density is sufficiently higher than that of the material of this deposition surface, and to the extent that only a single nucleus grows. If a crystal growth method is used in which a sufficiently small dissimilar material is formed and a crystal is grown around a single nucleus grown in this dissimilar material, the following 10,000 points will be obtained.

(1) The shape of the electrode with a pointed tip is determined by manufacturing conditions such as the deposition surface, the surface of different materials, the material of the electrode, and the deposition conditions, so that an electrode of a desired size can be formed, and the size It is possible to suppress the variation in

(2) Since the position of the electrode with the tip is determined by the positional accuracy of the surface of different materials, it can be manufactured at the desired position with high precision, and an electron emitting part with multiple electron emitting ports can be manufactured at a fine pitch. can do.

(3) In the p-type semiconductor region, a peak unique to a single crystal is formed, and the shape of the electron-emitting region is uniform and sharp, so special needle-like processing is not required, and the electric field strength can be evened out. It is also strong and suppresses variations in the operating start voltage range.
Furthermore, since conductivity can be improved, electron emission efficiency can be improved.

(4) It becomes easy to grow a single crystal even on the surface of an amorphous insulating material, where it has been difficult to grow a single crystal in the past, and an electron-emitting device with high breakdown voltage can be provided.

(5) Since it can be manufactured using a normal semiconductor manufacturing process, high integration can be achieved with a simple process.

A single crystal growth method for growing a single crystal on a deposition surface will be described in detail below.

First, we will discuss the selective deposition method that selectively forms a deposited film on the deposition surface. Utilizing the differences in influencing factors between materials,
This is a method of selectively forming a thin film on a substrate.

FIGS. 6(A) and 6(B) are explanatory diagrams of the selective deposition method.

First, as shown in FIG. 1A, a thin film 15 made of a material having different factors from that of the substrate 14 is formed on a desired portion of the substrate 14. Then, when a thin film made of a suitable material is deposited under suitable deposition conditions, the thin film 16t grows only on the thin film 15, as shown in FIG.
It is possible to cause the phenomenon that no growth occurs on the surface. By utilizing this phenomenon, it is possible to grow a thin film 16 formed in a self-aligned manner, and it becomes possible to use a conventional resist or to omit the conventional resist.

Examples of materials that can be deposited by such a selective formation method include Si02 for the substrate 14, Si, GaAs, and silicon nitride for the thin film 15, and Si, W, GaAs, and InP for the thin film 16 to be deposited.
etc.

FIG. 7 is a graph showing changes over time in the nucleation density of the 5i02 deposition surface and the silicon nitride deposition surface.

As the graph shows, 5i0
The nucleation density on 2 is saturated below 103 am-2,
The value hardly changes even after 20 minutes.

On the other hand, on silicon nitride (Si3N 4 ),
Once saturated at ~4 X 105 cm-2, then 1
It does not change for about 0 minutes, but increases rapidly after that.

Note that this measurement example shows the case where 5iCI4 gas was diluted with H2 gas and deposited by CVD under conditions of a pressure of 175 Tarr and a temperature of 1000°C. Other Si
A similar effect can be obtained by using H4, SiH2G+2, 5iHC13, SiF4, etc. as a reaction gas and adjusting pressure, temperature, etc. Vacuum deposition is also possible.

In this case, nucleation on Si02 is hardly a problem, but by adding MCI gas to the reaction gas,
Further suppressing nucleation on 02, Si on SiOz
It is possible to completely eliminate the accumulation of

This phenomenon is largely due to the difference in adsorption coefficient, desorption coefficient, surface diffusion coefficient, etc. for Si on the material surface of 5i02 and silicon nitride, but 5i02 reacts with the Si atoms themselves, and silicon monoxide, which has a high vapor pressure, The fact that this etching phenomenon does not occur in silicon nitride is thought to be a cause of selective deposition (T, Yonehara, S, Yoshioka).
,S.Miyazawa Journal ofA
pplied Physics 53. 8839
．． 1982).

In this way, if SiO2 and silicon nitride are selected as the materials of the deposition surface and silicon is selected as the deposition material,
As shown in the same graph, a sufficiently large difference in nucleation density can be obtained. Note that here, Si is used as the material for the deposition surface.
Although O2 is preferable, the difference in nucleation density can be obtained even with SiOx.

Of course, the material is not limited to these materials, and it is sufficient that the difference in nucleation density is 102 times or more in the density of nuclei, as shown in the same graph, and the deposited film can be Sufficient selection formation can be performed.

Another method for obtaining this difference in nucleation density is to locally implant ions of Si, N, etc. onto Si02 to
You may also form a region having the following.

By using such a selective deposition method and forming a foreign material with a nucleation density sufficiently higher than that of the material on the deposition surface in a sufficiently fine structure so that only a single nucleus grows, the presence of the fine foreign material can be reduced. It is possible to selectively grow single crystals only in certain locations.

The selective growth of single crystals depends on the electronic state on the surface of the deposition surface,
In particular, since it is determined by the state of dangling bonds, a material with a low nucleation density (e.g. Si02) does not have to be a bulk material, but can be formed only on the surface of any material or substrate to form the above-mentioned deposition surface. All you have to do is do it.

FIGS. 8(A) to (C) are formation process diagrams showing an example of a single crystal forming method, and FIGS. 9(A) and (B) are FIG. 3 is a perspective view of the substrate.

First, as shown in FIG. 8(A) and FIG. 9(A),
A thin film 18 with a low nucleation density that enables selective deposition is formed on the substrate 17, a thin film 18 with a high nucleation density is deposited on the thin film 18, and a different material 19 is patterned by phosphorography or the like. Form into minute minions. However, the size, crystal structure, and composition of the substrate 17 are arbitrary, and the substrate 17 may be a substrate on which a single functional element is formed.
It also includes an altered region having an excessive amount of Si, N, etc., which is formed by ion-implanting i, N, etc. into the thin WJ 18.

A single core of thin film material is then formed in only the dissimilar material 19 by suitable deposition conditions. That is, different materials 19
must be formed sufficiently finely so that only a single nucleus is formed. The size of the different material 19 varies depending on the type of material, but it may be several microns or less. Furthermore,
The nuclei grow while maintaining the single crystal structure and become island-shaped single crystal grains 20 as shown in FIG. 8(B). Island-shaped single crystal grain 2
0, as already mentioned, the thin film 1
It is necessary to determine conditions such that no nucleation occurs on 8.

The island-shaped single crystal grains 20 further grow around the dissimilar material 19 while maintaining the single crystal structure, and become a rotating single crystal 21 having a substantially conical pointed head, as shown in FIG. .

Since the thin film 18, which is the material of the deposition surface, is formed on the substrate l7, any material can be used for the substrate 17, which serves as a support, and furthermore, functional elements etc. can be formed on the substrate 17. single crystals can be easily formed thereon.

In the above example, the material of the deposition surface was formed from the thin film 18, but a single crystal may be similarly formed by using a substrate made of a material with a low nucleation density that allows selective deposition to be carried out in a circular manner. .

FIGS. 10(A) to 10(G) are forming process diagrams showing other examples of the single crystal forming method.

As shown in the same figure, by forming a sufficiently fine dissimilar material 19 on a substrate 22 made of a material with a low nucleation density to enable selective deposition, it is possible to easily perform the same process as in the example shown in FIG. Can form crystals.

(JJ, physical condition) Next, a specific method for forming the funeral crystal layer in the above example will be described.

The deposition surface material of the thin film 18 is Si02. Of course, a quartz substrate may be used, and metals, semiconductors, magnetic materials, piezoelectric materials,
An Si02 layer may be formed on the surface of an arbitrary substrate such as an insulator using a sputtering method, a CVD method, a vacuum evaporation method, or the like. Furthermore, although 5i02 is desirable as the deposition surface material, SiOx with a different value of X may also be used.

A silicon nitride layer (Si3 N 4 layer here) is formed on the Si02 layer 18 thus formed by low pressure vapor phase epitaxy.
Alternatively, a polycrystalline silicon layer is deposited as a dissimilar material, and the silicon nitride layer or polycrystalline silicon layer is patterned using conventional phosphorography techniques, X-rays, electron beams, ion beams, or lithographic techniques, preferably to a thickness of several microns or less. A minute dissimilar material 19 of ~17 layers m or less is formed.

Subsequently, )101 and H2, and 5i) l 2 C12
, 5iC14, 1SiHC10, SiF 4 or 5
i) selectively grow Si on the substrate 17 using a mixed gas with 14; The substrate temperature at that time is 700-11
00° C. and the pressure is about 100 Torr.

In a period of about several tens of minutes, a fine foreign material 19 of silicon nitride or polycrystalline silicon on SiO2 is formed! 1
20 grains of i-product Si! By using the optimum growth conditions, a single crystal 21 whose size ranges from about the size of the above-mentioned dissimilar material to about several tens of meters or more can be formed.

(Silicon nitride set rjt,) In order to obtain a sufficient nucleation density difference between the deposited surface material and the different material as described above, the composition of silicon nitride is not limited to Si3N4. It may be something that has been changed.

In the plasma CVD method, which forms a silicon nitride film at a low temperature by decomposing SiH4 gas and NH3 gas in RF plasma, by changing the flow rate ratio of SiH4 gas and NH3 gas, Si and Si in the deposited silicon nitride film are The composition ratio of N can be changed significantly.

FIG. 11 is a graph showing the relationship between the flow rate ratio of SiH4 and NH3 and the composition ratio of Si and N in the formed silicon nitride film.

The deposition conditions at this time were: RF output 175W, substrate temperature 38W.
The temperature was 0° C., the flow rate of SiH4 gas was fixed at 300 cc/min, and the flow rate of NH3 gas was varied. As shown in the same graph, when the gas flow rate ratio of NH3/SiH4 is changed from 4 to 10, the Si/N ratio in the silicon nitride film becomes 1.
．． It was revealed by Auger electron spectroscopy that the value varies from 1 to 0.58.

Now, low pressure CVD method SiH2G! 2 gas and NH3 gas were introduced, and the temperature was about 800°C under a reduced pressure of 0.3 Torr.
The composition of the silicon nitride film formed under the conditions is approximately stoichiometric, Si3N4 (Si/N ~0.75
) was close to

In addition, St is heated to about 1200°C in ammonia or N2.
A silicon nitride film formed by heat treatment (thermal nitriding method) can have a composition closer to the stoichiometric ratio because the formation method is carried out under thermal equilibrium.

When silicon nitride formed by the various methods described above is used as a deposition surface material with a Si nucleation density higher than 5i02 to grow the Si nuclei, a difference occurs in the nucleation density depending on the composition ratio.

FIG. 12 is a graph showing the relationship between St/N composition ratio and nucleation density. As shown in the graph, by changing the composition of the silicon nitride film, Si
The nucleation density of varies significantly. The nucleation conditions at this time were to reduce the pressure of 5iCI4 gas to 175 Tarr, and +oo
o'c to react with H2 to generate Si.

This phenomenon in which the nucleation density changes depending on the composition of silicon nitride affects the size of silicon nitride as a heterogeneous material that is formed finely enough to grow a single nucleus. That is, silicon nitride having a composition with a high nucleation density cannot form a single nucleus unless it is formed very finely.

Therefore, it is necessary to select the nucleation density and the optimum silicon nitride size for selecting a single nucleus. For example, for deposition conditions that yield a nucleation density of ˜10 cm −2 , single nuclei can be selected as long as the silicon nitride has a size of about 4 gm or less.

(Formation of different materials by ion implantation) As a method to realize a difference in nucleation density for Si, Si, N, P, B, F, Ar.

5i0 by ion implantation of He, C, As, Ga, Ge, etc.
An altered region may be formed on the deposition surface of No. 2, and this altered region may be used as the deposition surface material with a high nucleation density.

For example, a desired portion of the SiO2 surface is exposed to light, developed, and dissolved with a resist to partially expose the SiO2 surface.

Subsequently, using S i F4 gas as a source gas, S
i ion at 10keV lX l 016~LX10L
Implant into the SiO2 surface with a density of 8 cm-2. The projected range due to this is 1148, and the Si concentration reaches ~1022 cm-3 on the SiO2 surface.

Since 5i02 is originally amorphous, the region into which Si ions are implanted is also amorphous.

Note that to form the altered region, ion implantation can be performed using a resist as a mask, but focused ion beam technology can be used to form a focused S without using a resist mask.
i ions may be implanted into the SiO2 surface.

After performing the ion implantation in this manner, by peeling off the resist, an altered region containing excess Si is formed on the SiO2 surface. S is added to the SiO2 deposition surface where such altered regions are formed.
i by vapor phase growth.

:JSI3 diagram is a graph showing the relationship between Si ion implantation and cutting shape f&density.

As shown in the same graph, the larger the Si
& It can be seen that the density increases.

Therefore, by forming the altered region sufficiently finely, it is possible to use the altered region as a different material to make the nucleus of Si width 1&long, and to grow a single crystal as described above.

Note that forming the altered region sufficiently finely so that a single nucleus grows can be easily achieved by patterning the resist or narrowing down the focused ion beam.

(Sj deposition method other than CVD) To grow a single crystal by selective nucleation of Si, C
In addition to the VD method, St is processed in vacuum (< 10-6To
A method in which the material is evaporated using an electron gun and deposited on a heated substrate is also used. In particular, in ultra-high vacuum (<10-
' Torr)
In the ular beam epitaxy method, the Si beam and 5i02 begin to react at a substrate temperature of 900°C or higher,
It is known that Si nucleation on 5i02 is completely eliminated (↑, Yonehara, S., Yoshioka
andS, Miyazawa Journal of
Applied Physics 53°10, p6
839.1983).

Utilizing this phenomenon, we were able to form a single St nucleus with complete selectivity in minute silicon nitride dotted on 5iO2k, and grow single crystal Si there. The previous deposition conditions were a vacuum level of 10-8 Tarr or less, and a St beam intensity of 9.7 x 1014ato+ss/0m2m.
sec, and the substrate temperature was 900°C to 100°C.

In this case, due to the reaction 5i02 + Si-+ 29iO↑, a reaction product called SiO with a significantly high vapor pressure is formed, and as a result of this evaporation, 5i02 itself is etched by Si, whereas silicon nitride Above, the above-mentioned etching phenomenon does not occur, but nucleation and deposition occur.

Therefore, in addition to silicon nitride, tantalum oxide (Ta 20 s
), 'M silicon ugliness (SiON)? A similar effect can be obtained by using . That is, by micro-forming these materials to form the above-mentioned dissimilar materials, a single crystal can be similarly grown.

(Tungsten single crystal growth) The case of tungsten as a material other than Si will be exemplified.

Tungsten does not nucleate on Si02 and S
It is known that a polycrystalline film such as I, WSi 2 , PtSi, AI, etc. is deposited as a polycrystalline film. but,
According to the crystal growth method according to the present invention, a single crystal can be easily grown.

First, Si, WSi 2 , PtSi, or A is deposited on glass, quartz, thermal oxide film, etc. whose main component is 5i02.
1 is deposited by vacuum evaporation and patterned to a size of several ILm or less by photolithography.

Subsequently, it is placed in a reactor heated to 250-500°C, and a mixed gas of WF6 gas and hydrogen gas is heated to a pressure of 0.
Flow rates are 75 cc/win and 10 cc/sin, respectively, under reduced pressure of 1 to 10 Torr.

As a result, tungsten is produced as expressed by the reaction formula wF, +3H2→-+8HF. At this time, the reactivity between tungsten and 5i02 is extremely low and no strong bond occurs, so nucleation does not occur and therefore no deposition occurs.

On the other hand, Si, WSi 2 , PtSi, A
A tungsten nucleus is formed on I, but since it is formed finely, only a single tungsten nucleus is formed. Then, this single nucleus continues to grow, and Si02
It also grows horizontally as a single crystal. This is Si0
This is because tungsten nucleus growth does not occur on No. 2, so that it does not inhibit single crystal growth and become polycrystalline.

It should be noted that the combinations of the deposition surface material, different materials, and deposition materials described so far are not limited to those shown in each of the above examples, but it is clear that any combination of materials having a sufficient difference in nucleation density may be used. be.

Therefore, even in the case of a compound semiconductor such as GaAs or InP that can be selectively deposited by IR, a single crystal or a group of single crystals can be formed according to the present invention.

[Effects of the Invention] As described above in detail, according to the electron-emitting device according to the present invention, it is possible to reduce the voltage and also to improve the electron emission efficiency.

Note that in the present invention, a dissimilar material having a sufficiently higher nucleation density than the material of the deposited surface and sufficiently small enough to grow only a single nucleus is formed on the deposition surface, and a long monomer of I& length is formed on this dissimilar material. If an electrode having a pointed head is formed using a crystal growth method in which a crystal is grown around one nucleus, the following effects will occur.

(1) The shape of the mandrel with the pointed head is determined by manufacturing conditions such as the deposition surface, dissimilar material surface, electrode material, and deposition conditions;
Electrodes of a desired size can be formed, and variations in the size can be suppressed.

(2) Since the position of the electrode with the pointed head is determined by the positional accuracy of the surface of different materials, it can be manufactured at the desired position with high precision, and the electron emitting part with multiple electron emitting ports can be formed with a 7-inch pitch. It can be made.

(3) In the p-type semiconductor region, a peak unique to a single crystal is formed, and the shape of the electron-emitting region is uniform and sharp, so special needle-like processing is not required, and the electric field strength can be evened out. It is also strong and suppresses variations in the operating start voltage range.
Furthermore, since conductivity can be improved, electron emission efficiency can be improved.

(4) It becomes easy to grow a single crystal even on the surface of an amorphous insulating material, where it has been difficult to grow a single crystal in the past, and an electron-emitting device with high breakdown voltage can be provided.

(5) Since it can be manufactured using a normal semiconductor manufacturing process, high integration can be achieved with a simple process.

[Brief explanation of drawings]

FIG. 1 illustrates an embodiment of the electron-emitting device of the present invention [! 11
FIG. FIG. 2 is an explanatory diagram of the operation of the above embodiment. FIG. 3(A) is an energy band diagram of the present embodiment in an equilibrium state, and FIG. 3(B) is an energy band diagram of the non-embodiment during operation. FIG. 4 is an energy band diagram of a metal-semiconductor junction. FIG. 5 is an energy band diagram of the semiconductor surface in the present invention. FIGS. 6(A) and 6(B) are explanatory diagrams of the selective deposition method. FIG. 7 is a graph showing changes over time in the nucleation density of the SiO2 deposition surface and the silicon nitride deposition surface. FIGS. 8(A) to 8(C) are formation process diagrams showing an example of a method for forming a single crystal. 9(A) and 9(B) are perspective views of the substrates in FIG. 8(A) and FIG. 8(G). FIGS. 10(A) to 10(C) are forming process diagrams showing other examples of the single crystal forming method. FIG. 11 is a graph showing the relationship between the flow field ratio of 5fH4 and NH3 and the composition ratio of Si and N in the formed silicon nitride film. FIG. 12 is a graph showing the relationship between the Si/N composition ratio and the nucleation density. FIG. 13 is a graph showing the relationship between the implantation amount of St ions and the cutting J&density. FIG. 14 is a schematic partial cross-sectional view showing an example of a field effect type electron-emitting device. 1... Oxidized substrate 2. Fist... Nucleation base 3.5... Conductive layer 4.6.7 - Fist. Φ Insulating layer 8. Fist fight. 0. Conductive region 9. ...Low work function material region 10...P-type semiconductor region 11...N-type semiconductor region 12...Extraction electrode 13...φ... Electrode agent having a pointed end Patent Attorney Jo Taira Yamashita Figure 1 Figure 2 Figure 3 (A) (B) Figure 4 Figure 5 Figure 6 (A) Closed (off $9 Figure (A) (E3) $11 Figure NH3 /51H4 capacity ratio 0 0.5
1, O5i/N Child and Han Otsu No. 13 Figure 1Q1610171018

Claims (5)

[Claims] (1) In an electron-emitting device having an electrode having a pointed head provided on a deposition surface, and an extraction electrode provided on the deposition surface and near the pointed end, the pointed end of the electrode An electron-emitting device comprising at least a semiconductor crystal produced by nuclear growth and a low work function material. (2) The pointed portion has a p-type semiconductor region and a low work function material bonded to the p-type semiconductor region, and a reverse bias voltage is applied to the junction, and NEA (negative electron affinity) is applied. 2. The electron-emitting device according to claim 1, wherein electrons injected into the p-type semiconductor are emitted from the surface of the low work function material by utilizing the state. (3) The semiconductor crystal is provided on the deposition surface with a dissimilar material having a sufficiently higher nucleation density than the material of the deposition surface and sufficiently small to the extent that only a single nucleus grows, and the semiconductor crystal grows on the dissimilar material. 3. The electron-emitting device according to claim 1, wherein the electron-emitting device is formed of a single crystal grown from a single nucleus. (4) The electron-emitting device according to claim 3, wherein the deposition surface is formed on a desired base material. (5) The electron-emitting device according to claim 3, wherein the deposition surface is an amorphous insulating material.