JPH03291980A - Diamond semiconductor element and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a diamond semiconductor element having excellent rectifying characteristic and realizing an excellent blue light emission by providing a layer of specific composition made of metal such as Al, etc., partial oxide of semimetal such as Si, etc., and/or partial nitride in a boundary between diamond semiconductor and an electrode. CONSTITUTION:Mixture gas of Co and H2 is fed under the conditions of 900 deg.C of a substrate temperature, 350W of microwave output and 40Torr of pressure on a substrate 1 to form a diamond thin film 2. Then, an Al partial oxide layer 3 is formed on the thin film by a vacuum depositing method. The thickness of the oxide film is set to 3000Angstrom or less. Thereafter, Al is deposited on the oxide layer to form an electrode 4. The layer 3 is formed of an intermediate layer made of metal such as Al, etc., partial oxide of semimetal such as Si, etc., and/or partial nitride, and formal valence of the metal or the semimetal of the partial oxide is 80% or less of the normal saturated valence of the metal or semimetal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a diamond semiconductor element and a method for manufacturing the same, and more particularly, to various semiconductor devices such as tie-outs, transistors, light-emitting elements, and light-receiving elements, especially at high temperatures. The present invention relates to a highly practical diamond semiconductor element that can be suitably used as various semiconductor devices that can be used even under harsh conditions such as under radiation, and a practically advantageous manufacturing method thereof.

[Prior art and problems to be solved by the invention] Diamond is generally used as an insulating material, but
Recently, by doping diamond with impurities such as boron and phosphorus, py! 1. It has been revealed that diamond can be used as an n-type semiconductor material, and research and development of various diamond semiconductor elements is progressing.

The operating temperature limit for conventional semimetal semiconductor devices, such as Si-based semiconductor devices, is 150°C, and GaAs
All diamond semiconductors have low operating temperatures, with a limit of 250° C., whereas diamond semiconductors are expected to be devices that can operate even at temperatures higher than the operating temperature.

Furthermore, among conventional semiconductor light emitting devices, a practical high-brightness blue light emitting device is known, and it is expected that a blue light emitting device can be realized by using a diamond semiconductor.

For example, a group from Osaka University's Faculty of Engineering, Osaka Diamond Co., Ltd., and Idemitsu Petrochemical Co., Ltd. confirmed rectification and blue light emission in a Schottky junction diode with a point contact electrode that uses a p-type polycrystalline diamond thin film. (Proceedings of the Japan Society of Applied Physics, Heii 1st year: 2a-N-7
) However, in this case, it is difficult to process the tip of the needle for point contact, the characteristics of the element are unstable, and the device structure becomes complicated. There is also a problem in that it is difficult to put it into practical use.

On the other hand, the Sumitomo Electric Industries, Ltd. group formed a diamond semiconductor layer doped with boron on high-pressure synthetic diamond, provided Ti and W electrodes on the surface, and formed a Schottky junction with the W electrode. Blue light emission has been confirmed in the device (Proceedings of the Japan Society of Applied Physics 1989: 2a-N-9). However, in this device, there is no W between the W electrode and the diamond semiconductor layer.
There are problems in that carbonization tends to occur and the characteristics of the device become unstable, and in addition to this problem, there is also the problem that it is extremely difficult to form electrodes stably.

In addition, as a related technology, for example, JP-A-1-10
No. 2893 discloses an MIS type light emitting diode, but in this device, the diamond layer is an insulating layer made of non-doped diamond and is excluded from the diamond semiconductor device.

The present invention has been made in view of the above circumstances.

An object of the present invention is to exhibit excellent characteristics as a semiconductor device, such as particularly good rectification properties, or the ability to realize excellent blue light emission depending on the structure of the device, and also to have excellent stability. It has the advantage of being able to operate under harsh environmental conditions such as high temperatures and radiation, and is a practical device that can be suitably used as various semiconductor devices such as diodes, transistors, light emitting elements, and light receiving elements. The object of the present invention is to provide a diamond semiconductor element of a high quality and a method of manufacturing the same which is practically advantageous.

[Means for Solving the Problems] As a result of intensive research aimed at solving the above-mentioned problems and realizing practical diamond semiconductor elements, the present inventors have developed various configurations using diamond semiconductor layers. A diamond semiconductor device in which a layer of a specific composition consisting of a partial oxide and/or partial nitride of a metal such as A1 or a semimetal such as St is provided at the interface between the diamond semiconductor and the electrode, or I found that it satisfies the following.

In addition, as a result of various studies regarding a suitable manufacturing method for this diamond semiconductor element, we have found that a diamond semiconductor layer is formed on a substrate by a vapor phase synthesis method to form a layer consisting of a partial oxide and/or partial nitride of a metal or metalloid. It has been found that a specific method of sequentially forming layers by a vapor phase method and further providing electrodes is advantageous in practice.

The present inventors have completed the present invention based on these findings.

That is, the present invention provides an intermediate layer consisting of a partial oxide of a metal or a partial nitride thereof, and/or a partial oxide of a metalloid or a partial nitride thereof, at the interface with the diamond semiconductor device electrode. This is a characteristic diamond semiconductor element.

Further, the present invention provides a method for manufacturing the diamond semiconductor element of the present invention that is practically advantageous, in which a diamond semiconductor layer is formed on a substrate by a vapor phase synthesis method, and then a diamond semiconductor layer is formed along with a metal or semimetal in an oxygen reservoir. It is characterized by forming an intermediate layer made of a partial oxide and/or partial nitride by a gas phase method using a gas or oxide and/or a nitrogen source gas or nitride, and then forming an electrode. This is a method for manufacturing a diamond semiconductor element.

The present invention will be explained in more detail below.

The diamond semiconductor used in the diamond semiconductor element of the present invention can take various forms as long as it exhibits properties as a semiconductor. For example, it may be a nil semiconductor or a p-type semiconductor doped with appropriate impurities. Alternatively, it may be a semiconductor that is not particularly doped. Depending on the purpose, these may also be used in an appropriate combination.

Any of natural diamonds and synthetic diamonds obtained by various methods such as known vapor phase synthesis methods such as μ plasma CVD method can be used as the diamond semiconductor in the present invention, and these may be used depending on the purpose. They can also be used in appropriate combinations.

When using the impurity, there are no particular restrictions on the doping method, and n may be doped by various methods such as known methods.
l! ! , can be made into a p-type semiconductor, etc. For example, doping the various types of diamonds with boron (B) etc. can make them into pHl diamond semiconductors, while doping them with pentavalent elements such as nitrogen (N) and phosphorus (P) allows n It is also possible to use a type diamond semiconductor.

That is, the diamond used in this diamond semiconductor or the diamond used as its raw material may be in the form of a single crystal, polycrystal, thin film, etc.
It may contain an amorphous component such as a diamond-like film, and there are no particular restrictions on the method of converting it into a semiconductor.

There are no particular restrictions on the shape of the diamond semiconductor, and it can be used in the form of chips or layers (including thin films, hereinafter the same) in various shapes, but it is usually used, for example, on the entire surface of a suitable substrate or in the form of a layer. It is used by forming a layered structure (such as a thin film) on a surface of a predetermined portion to form a layered structure (such as a thin film) with an appropriate surface shape.

When this diamond semiconductor is formed into a layer, there is no particular limit to its thickness, but in the present invention, the thickness of the diamond semiconductor is as follows.

Usually, it is set in the range of iooλ to 1100B.

In the present invention, the diamond semiconductor may be provided on the substrate depending on the purpose, or may not be provided on the substrate.

There are no particular restrictions on the substrate used or the material constituting the substrate, and examples include various semiconductor materials such as Si, Ga, BN, GaAs, SiO, Ale 03, AJ.
IN, various glasses, various insulating materials such as diamond, carrier metals such as An, W, Mo, Ti, SUS, W
Any conductive materials such as alloys such as C and WC-Co can be used. For these substrates, an insulating material or a conductive material may be appropriately selected depending on the intended device configuration.

Note that these substrates may have a single layer structure, or may have a multilayer (laminated) structure of two or more layers.

The configuration of the substrate may be appropriately selected depending on the purpose of use, etc., and an appropriate Jl (sublayer, etc.) may be provided at the interface between the substrate and the diamond semiconductor as desired. for example.

A diamond layer is provided on the various substrate materials.

The diamond layer may be formed as a sublayer on a predetermined surface of the diamond layer, such as another diamond semiconductor layer doped with an impurity such as B.

The diamond semiconductor layer or the surface on which the diamond layer is provided, such as the substrate, may be appropriately treated to remove surface scratches as described below.

One of the important points in the diamond semiconductor device of the present invention is that a partial oxide of a metal or a partial nitride thereof, and/or a partial oxidation of a semimetal is present at the interface between the diamond semiconductor such as the diamond semiconductor layer and the electrode. The point is to provide an intermediate layer made of a substance or a partial nitride thereof.

Examples of the metal or semimetal used as the partial oxide or partial nitride include B, A11. Ga
, In, Si, Ge, Sn, Pb, As, Sb, Bi
, Se, Te, Cu.

Zn, Cd, Sc, Y, various lanthanide elements, U, T
i, Zr, If, V, Nb, Ta, Cr, Mo, W
, Mn, Fe, etc. Among these, Ai and St are particularly preferred. These may be used alone or in combination of two or more, and if desired, a composite partial oxide such as 5iAjlON or It can also be used as a partial nitride.

The partial oxide of the metal or metalloid is such that the formal valence of the metal or metalloid in the partial oxide is such that the metal or metalloid normally has a stoichiometric ratio of saturated (complete) oxide S (e.g. , Al.

03, Si Ot, etc.) (hereinafter this is usually referred to as saturated valence; for example, Ai and St
In the case of , the usual saturated valences are 3 and 4, respectively. ) has a composition smaller than the valence of
In particular, it is preferable that the formal valence of the metal or metalloid in the partial oxide is 80% or less, particularly 70 to 1%, of the normal saturated valence of the metal or metalloid.

For example, in the case of a partial oxide of Al, when expressed by a formal composition formula (Ait oy ), y is a real number less than 3 and larger, but usually the range of y is 2.4 or less, Preferably it is 2.1 to 0.03, and in the case of a partial oxide of Si, when this is expressed by the formal compositional formula (SiO,), X is a real number less than 2 and larger than O. Normally, the range of X is 1.5 or less, preferably 1.4 to 0.
．． It becomes 02.

Further, in the partial nitride of the metal or metalloid, the formal valence of the metal or metalloid in the partial nitride is
It is preferable that the valence of nitrogen (N) in the partial nitride is 80% or less, particularly 70 to 1%, of the saturated valence of the metal or metalloid as defined above.However, the valence of nitrogen (N) in the partial nitride is 3 (or -3).

Therefore, in the case of partial nitride of AIL, when expressed by the formal compositional formula (A-Nh), k is less than 1 and 0
Although the real number is larger, it is usually 0.8 or less, preferably 0.7 to 0. Oo, and in the case of Si partial nitride, when expressed by the formal compositional formula (Si*Nj〉),
Although j is a real number less than 4 and greater than 0, the range of J is usually 3.2 or less, preferably 2.8 to 0.04.

Note that the intermediate layer made of the partial oxide and/or partial nitride may be composed of one or more kinds of the partial oxide, or may be composed of one or more kinds of the partial nitride. or,
It may be in a mixed state, such as a composite or composition of one or more partial oxides and one or more partial nitrides, or, if desired, Other components may be included within the range.

Is there any particular limit to the thickness of the intermediate layer made of partial oxide and/or partial nitride?

Normally, it is appropriate to make it 3,000 Å or less, and there is no particular limit to the lower limit of the thickness, and it can be selected appropriately depending on the purpose of use, but the lower limit is usually about 50 pieces. suitable. However, the preferred thickness of the intermediate layer is z, ooo to 200 people.

If the thickness of this intermediate layer is too large, sufficient current may not flow. Furthermore, if the thickness is too small, the intended purpose of the present invention may not be fully achieved.

In the diamond semiconductor device of the present invention, the method for forming the intermediate layer made of the partial oxide and/or partial nitride is not limited to #, and various methods such as known methods can be employed.

A preferred forming method in the present invention will be described later.

In the diamond semiconductor device of the present invention, an electrode is provided at least on the surface of the intermediate layer made of the partial oxide and/or partial nitride. Note that the electrode provided on the surface of the intermediate layer may extend on the surface of the diamond semiconductor such as the diamond semiconductor layer or on another surface.

These electrodes vary depending on the purpose of use of the device.

The MI
It can be provided in an S-type joining format. By appropriately selecting the configuration, electrodes, and arrangement of the elements in this way, various diodes such as MISyJ diodes, MIS type transistors (FET),
It can be configured or used as various transistors such as static induction transistors (SIT), light emitting devices, light receiving devices, and the like.

The material of the electrode is not particularly limited, and various known materials can be appropriately selected and used. Specifically, examples thereof include metals and alloys such as All, W, and Ti, conductive compounds such as silicide, and conductive inorganic polymers such as polysilicon.

The method for forming the electrode is not particularly limited, and examples include vapor deposition, ion blating, sputtering,
Various methods such as known vapor phase methods such as various CVD methods can be appropriately employed.

In particular, the diamond semiconductor element of the present invention is characterized by having a layer made of a metal partial oxide and/or partial nitride at the interface between a diamond semiconductor such as a diamond semiconductor layer and at least one electrode. It exhibits excellent characteristics as a semiconductor device, such as having good rectification properties and being able to generate excellent blue light emission depending on the structure of the device, and also has excellent stability in terms of device structure and characteristics. In addition, it is a practically excellent element that has the advantage of being able to operate under harsh environmental conditions such as high temperatures and radiation. It can be suitably used as a semiconductor device.

The diamond semiconductor element of the present invention can be manufactured using the novel method of the present invention described above. , using an oxygen source gas or oxide and/or a nitrogen source gas or nitride.

A method for manufacturing a diamond semiconductor device, which comprises forming an intermediate layer made of a partial oxide and/or a partial nitride by a vapor phase method, and then forming an electrode.
It is manufactured suitably for practical purposes.

The method of the present invention will be explained in detail below.

In the method of the present invention, it is preferable to use a substrate made of a low-resistance substrate material among the various substrate materials exemplified above, that is, a low-resistance substrate.

This low-resistance substrate may be appropriately selected from the above-mentioned semiconductor materials such as silicon wafers, the above-mentioned insulating materials such as various glasses, or the above-mentioned conductive materials such as AfL substrates. I can do it.

In the method of the present invention, a diamond thin film as a diamond semiconductor layer is formed on the surface of the substrate by vapor phase synthesis.

Note that, when forming this diamond thin film, the substrate may be subjected to an appropriate surface scratch treatment in advance. This surface damage can be treated by various methods such as known methods. Specifically, for example, diamond, Si, etc., with a powder particle size of 100 gm or less
For example, a method of dispersing the powder in a liquid medium and scratching the surface by ultrasonication using a (7) powder such as C, BN, polishing, and lapping can be mentioned.

As a method for forming a diamond thin film by the vapor phase synthesis method, various methods such as well-known methods can be appropriately employed.

Specifically, for example, using various carbon source-containing gases such as CO/H* mixed gas, mixed gas of carbon I1m gas such as lower hydrocarbon gas such as methane, and Hyo, etc., Examples include various CVD methods such as plasma CVD method and thermal plasma CVD method, and various methods such as various PVD methods. The diamond thin film thus formed may be in any form, such as polycrystalline, single crystal, or diamonds containing amorphous components. As described above, if necessary, it can be doped with an appropriate impurity to make it a p'll or n-type semiconductor. Incidentally, if the formed diamond thin film does not require doping but a portion or all of it has properties as a semiconductor, it may be used as is without necessarily performing the doping.

The thickness of the formed diamond thin film can be appropriately selected depending on the purpose of use, but the thickness of the portion used as the diamond semiconductor layer may normally be selected within the above-mentioned range.

In the method of the present invention, an intermediate layer made of the partial oxide and/or partial nitride is formed on at least a desired surface of the diamond semiconductor layer of the diamond thin film.
It is formed by a vapor phase method using the metal and/or metalloid and an oxygen source gas or its oxide, and/or the metal and/or metalloid and a nitrogen source gas or nitride.

Note that when forming this intermediate layer made of partial oxide and/or partial nitride, a pretreatment of polishing and/or chemical etching (in gas phase or liquid phase) on the desired surface of the diamond thin film is performed in advance. You can leave it there.

The metal used in forming the intermediate layer made of the partial oxide and/or partial nitride by this vapor phase method may include the various metals listed above (semimetals may also be used).
), one or more of them can be used.

The oxygen source gas is usually oxygen (08) or an oxygen (Ol)-containing gas (for example, air, a mixed gas of oxygen and an inert gas such as argon, helium, or nitrogen).
I can list many things.

Examples of the nitrogen source gas include nitrogen, ammonia, amines, and a mixed gas of these with H3 and the above-mentioned inert gas.

As the oxides and nitrides, oxides and nitrides of the same metal as the metal used (or other metals as necessary) can be used as appropriate.

For example, when forming a partial oxide of Ai, the raw materials include AiL and A jl *Os! l combination, or a combination of /11 and 02, or even A
A combination of i, An, 03, and 0□ is suitable.

There are no particular limitations on the method for forming the intermediate layer made of partial oxide and/or partial nitride, and the various methods exemplified above can be employed as appropriate.

The thickness of the intermediate layer made of partially oxidized EL and/or partially nitride thus formed is as described above.

In the method of the present invention, an electrode is formed on a desired surface of the intermediate layer made of partial oxide and/or partial nitride formed as described above. Note that the electrodes may be provided extending on other desired surfaces as described above.

There are no particular limitations on the material, structure/system, formation method, etc. of the electrodes, and these can be as described above.

In the method of the present invention, after forming the electrodes, other processes such as various workings and treatments necessary for constructing the intended element can be performed.

In this way, various diodes such as MISfi diodes, MISI! ! ) Run Sister (FE
T), various transistors such as static induction transistors (SIT), and various semiconductor devices such as light emitting elements and light receiving elements.

In the manner described above, the diamond semiconductor element of the present invention can be advantageously manufactured.

[Example] Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these Examples and may be modified as appropriate within the scope of the gist of the present invention. It can be modified or applied.

(Example 1) Low resistance substrate (specific resistance, 0.001 to 0.02Ω・cm)
A silicon wafer was placed in acetone in which diamond particles having a particle size of 5 to 12#L111 were dispersed, and the surface of the substrate was treated with ultrasonic waves for 30 minutes to remove scratches on the surface of the substrate.

Next, CO was applied onto the surface of the substrate at a substrate temperature of 900°C, a microwave output of 350 W, and a pressure of 40 Torr.
A mixed gas of H2 and H2 (Co/H1-7/93 molar ratio) was passed through, and a diamond thin film having a thickness of 3 μm was formed over 4 hours.

Next, on the surface of this diamond thin film, an An partial oxide layer [(All+O) layer] was formed by vacuum evaporation using Af and AiL 03 as raw materials. The thickness of this partial oxide layer was approximately 400-1,0 (10 people).

Next, a hole mask with a hole diameter of 1 mm was attached on the surface of the partial oxide layer, and An was vapor-deposited to form an electrode with a film thickness of 1.000 mm.

In addition, silver paste was applied to the back surface of the silicon urchin serving as the low resistance substrate, and this was used as the other electrode to produce a diamond semiconductor element (test element) having the configuration shown in FIG. 1.

In FIG. 1, l is the substrate (in this example, the silicon wafer which is a low resistance substrate), 2 is the diamond semiconductor layer (in this example, the diamond thin film), and 3 is the partial oxide layer (in this example, the A1 4 is an electrode (in this example, the A-deposited layer), 5 is an electrode (this An example is the silver paste calendar).

The current-voltage characteristics (IV characteristics) of the diamond semiconductor device (test device) produced as described above were measured.

The results are shown in Figure 2(b). In Figure 2(b), the solid line in the figure represents the IV characteristic curve when voltage was applied in the forward direction, and the broken line represents the IV characteristic curve when voltage was applied in the reverse direction. The rectification ratio of the element was estimated from these two IV characteristic curves showing the actual IV characteristic curves, and the results are shown in Table 1.

On the other hand, in order to investigate the composition and thickness of the partial oxide layer, etc. of the device, Auger electron spectroscopy [using an Auger microprobe (JAlP-7100) manufactured by JEOL Ltd.] was used to investigate the composition in the depth direction from the An electrode surface. 1. (Element content *) was measured. The results are shown in Figure 2 (a).
), the horizontal axis represents the sputtering time (minutes) corresponding to the depth direction, and the vertical axis represents the distribution of each element (relative concentration mol %).

Furthermore, from this FIG. 2(a), the AfL electrode layer (electrode 4),
A11 Partial oxide layer (partial oxide layer 3) thickness and A
The composition (element ratio in the depth direction) of the n-part oxide layer (partial oxide layer 3), etc. can be seen.

The composition of the AU partial oxide layer (partial oxide layer 3) is shown in Figure 2 (
As shown in a), it changes somewhat along the depth direction, so
Element ratio Air at the depth where oxygen (0) concentration is maximum
o (generally, metal M: oxygen 0, or metal M: nitrogen N) was taken as a representative value of the composition of a partial oxide layer (in the general formula, an intermediate layer consisting of a partial oxide and/or a partial nitride). .

Table 1 shows the composition of the An partial oxide layer determined by this Auger electron spectroscopy (composition as the representative value = A:O).

Note that in the test element in the example, no special surface treatment was performed on the diamond film surface before the partial oxide intermediate phase was formed.

However, due to the minute irregularities on the diamond surface,
It is recognized that the results of Auger electron spectroscopy are not complete elemental analysis results, and that the noise level does not completely match 0%.

(Example 2) A device was manufactured in the same manner as in Example 1, except that the conditions for forming the partial oxide layer were changed to form a partial oxide of An, and the device was manufactured in the same manner as in Example 1. I-V characteristics,
The element distribution in the depth direction was measured, and the rectification ratio and the composition of the m-minute oxide layer (representative value AJl: O) were estimated.

The results are shown in Figure 113 (b), Figure 3 (a), and Table 1, respectively.

(Example 3) A device was manufactured in the same manner as in Example 1, except that the conditions for forming the partial oxide layer were changed to form a partial oxide of Ai in Example 1. I-V characteristics,
The element distribution in the depth direction was measured, and the rectification ratio and the composition of the partial oxide layer (representative value Ajl:O) were estimated.

The results are shown in Figure 4(b) and JF1411g(a), respectively.
, and shown in Table 1.

(Example 4) In Example 1, the partial oxide layer (partial oxide layer 3) was formed using Si instead of An, and St O instead of Al*Os, The same procedure was carried out except that a St partial oxide layer was formed in place of the Ai partial oxide layer.
A device was prepared in the same manner as in Example 1, and the IV characteristics and elemental distribution in the depth direction of the device were measured in the same manner, and the rectification ratio and the composition of the partial oxide layer (typical value 5ilo) were estimated.

The results are shown in FIG. 5(b), FIG. 5(a), and Table 1, respectively.

(Considerations) From the above results, the elements of Examples 1.2 and 4 whose partial oxide composition [metal (All or Si): oxygen (0), that is, the formal valence of the metal] are within the above-mentioned preferred range. It can be seen that in some cases, an extremely good rectification ratio is exhibited. The device of Example 3 is as follows.

Although the rectification ratio is not very large because the composition of the partial oxide (AiL: O, ie, formal metal atoms 11l) is not within the above-mentioned preferred range, it can be seen that it exhibits rectification properties.

(The following is a blank space) Table 1 Metal: Oxygen Comments based on 1-V characteristics Example I Al: 0 4 to 5 digits = 100:96
(Good) Example 2 11:o 5-6 digits = 1001 pieces
(Good) Example 3 Ai:O rectification = 100:19 (Small) Example 4 Si: 0 3 to 4 digits = loo: 116 Book 1 Representative value of the composition of the partial oxide layer by Auger electron spectroscopy (definition) (See the main text of Example 1.) [Effects of the Invention] According to the present invention, an intermediate layer made of a partial oxide and/or a partial nitride (particularly a specific metal: Particularly good rectification properties are provided because an intermediate layer consisting of a partial oxide and/or partial nitride of a metal having a specific formal valence range, such as a partial oxide layer with an oxygen composition, or Depending on the structure of the device, it exhibits excellent characteristics as a semiconductor device, such as being able to emit excellent blue light, and is also highly stable, and can operate under harsh environmental conditions such as high temperatures and radiation. It is possible to provide a diamond semiconductor element of a practical level that takes advantage of the advantages and can be suitably used as various semiconductor devices such as diodes, transistors, light-emitting elements, light-receiving elements, and the like.

Further, according to the present invention, as a preferred method for manufacturing the diamond semiconductor element of the present invention, a diamond semiconductor layer is formed on a substrate by a vapor phase synthesis method, and an intermediate layer made of a partial oxide and/or a partial nitride is formed by a vapor phase synthesis method. Sequentially form 1
Since a specific method of subsequently forming an electrode (layer) is adopted, a practically advantageous method for manufacturing a diamond semiconductor element can also be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the structure of a diamond semiconductor element of the present invention. 2(a) to 5(a) show the element distributions in the depth direction of the device from the electrodes (A!L electrodes) in the devices of Examples 1 to 5 according to the present invention, respectively, using Auger electron spectroscopy. It is a graph showing the results measured by. The horizontal axis of each graph indicates the sputtering time (minutes) corresponding to the depth direction, and the vertical axis indicates the element distribution [concentration of each element (mol %)]. ! Fig. s2 (b) to Fig. 5 (b) are characteristic diagrams showing the current-voltage characteristics of the elements of Examples 1 to 5 according to the present invention, respectively. DESCRIPTION OF SYMBOLS 1...Substrate, 2...Diamond semiconductor element layer, 3
...Partial oxide layer, 4: Electrode (calendar), 5: Electrode layer. Figure 2 (0) Sputter lip clear space c minutes) Figure 3 (a) Sukhatontanog>8'T interval (minutes) (b) VOLTAGE (Volt) (b) VOLTAGE (Volt) Figure 4 (0) Sl (Tsutano time (minutes) Figure 5 (a) Switch time (minutes) (b) VOLTAGE (Volt) (b) VOLTAGE (Volt)

Claims (5)

[Claims] (1) A diamond characterized by having an intermediate layer consisting of a metal partial oxide or its partial nitride, and/or a metalloid partial oxide or its partial nitride at the interface between the diamond semiconductor and the electrode. semiconductor element. (2) The diamond semiconductor device according to claim 1, wherein the metal is Al and the semimetal is Si. (3) The formal valence of the metal or metalloid in the partial oxide or partial nitride is 8 of the valence when the metal is in a saturated oxide state with a normal stoichiometric ratio.
3. The diamond semiconductor element according to claim 1, wherein the diamond semiconductor element has a content of 0% or less. (4) The diamond semiconductor device according to any one of claims 1 to 3, wherein the intermediate layer has a thickness of 3,000 Å or less. (5) After forming a diamond semiconductor layer on the substrate by a vapor phase synthesis method, it is partially formed by a vapor phase method using an oxygen source gas or oxide and/or a nitrogen source gas or nitride together with a metal or metalloid. 5. The method of manufacturing a diamond semiconductor device according to claim 1, further comprising forming an intermediate layer made of an oxide and/or a partial nitride, and then forming an electrode.