Semiconductor device, electronic apparatus, diamond wafer, and method for manufacturing semiconductor device

Abstract

The purpose of the present invention is to improve the performance of a semiconductor device including a resistance element having diamond to which a conductivity type impurity is introduced. In the present disclosure, a diamond substrate is prepared (S101). Next, the upper surface of the diamond substrate is polished (S102). Thereafter, polishing defects formed by polishing the upper surface of the diamond substrate are removed (S103). Then, the upper surface of the diamond substrate is cleaned (S104). Subsequently, a diamond with a conductive impurity introduced is formed on the upper surface of the diamond substrate (S105). At this time, in the step of forming the diamond into which the conductivity type impurity is introduced, the temperature is feedback-controlled, and the diamond to which the conductivity type impurity is introduced is formed by a plasma CVD method while controlling the introduction amount of the conductivity type impurity.

Description

Semiconductor device, electronic device, diamond wafer, and method for manufacturing semiconductor device

[0001] The present invention relates to a semiconductor device, an electronic device, a diamond wafer, and a manufacturing technique for the semiconductor device, and relates to a technique that is effective when applied to, for example, a semiconductor device including a resistance element having diamond doped with conductive impurities.

[0002] Japanese Patent Application Laid-Open No. 2018-12611 (Patent Document 1) describes a technique for providing impurity-doped diamond with low electrical resistance.

[0003] JP 2018-12611 A

[0004] For example, diamond has the highest thermal conductivity of any material (four times that of SiC and 16 times that of GaN) and the highest breakdown field strength of any semiconductor material (three times that of SiC and 10 times that of GaN). Furthermore, the hole mobility and hole saturation velocity in diamond are comparable to those of silicon.

[0005] Therefore, diamond is expected to improve the performance of semiconductor devices. In this regard, research is underway to construct field effect transistors included in semiconductor devices from diamond transistors. Meanwhile, components of semiconductor devices include not only field effect transistors but also resistor elements. For this reason, research is also being conducted to realize resistor elements that have diamond doped with conductive impurities.

[0006] However, with current technology, it is difficult to precisely control the concentration of conductive impurities introduced into diamond, which hinders the progress of practical device applications. For this reason, there is a demand for substrates with controlled concentrations of conductive impurities.

[0007] A semiconductor device according to one embodiment includes a resistor element having a diamond doped with a conductive impurity, the resistor element having a resistance value within a range of ±50% of a reference value.

[0008] In one embodiment, the semiconductor device includes a resistor element having diamond doped with conductive impurities, the concentration of which is within a range of ±65% of a reference value.

[0009] In one embodiment, the semiconductor device includes a voltage amplifier. The voltage amplifier includes a load resistor element and a transistor connected in series with the load resistor element. The load resistor element includes diamond doped with a conductive impurity. The transistor is a diamond transistor.

[0010] In one embodiment, a semiconductor device includes a resistor element formed on a diamond substrate and a transistor formed on the diamond substrate. The resistor element includes diamond doped with conductive impurities. The transistor is a diamond transistor.

[0011] In one embodiment, the diamond wafer has a plurality of chip regions, each of which includes at least a resistor element having diamond doped with conductive impurities and a transistor formed of a diamond transistor.

[0012] An electronic device according to one embodiment includes the above-described semiconductor device as a component.

[0013] In one embodiment, the method for manufacturing a semiconductor device comprises the steps of: (a) preparing a diamond substrate; (b) polishing the top surface of the diamond substrate; (c) removing polishing defects; (d) cleaning the top surface of the diamond substrate; and (e) forming a diamond doped with conductive impurities on the top surface of the diamond substrate. In step (e), the diamond doped with conductive impurities is formed by plasma CVD while feedback-controlling the temperature and controlling the amount of conductive impurities introduced.

[0014] According to one embodiment, it is possible to improve the performance of a semiconductor device including a resistance element having diamond doped with conductive impurities.

[0015] FIG. 1 is a circuit diagram of a voltage amplifier. FIG. 2 is a flowchart showing the flow of steps for realizing the basic concept. FIG. 3 is a diagram showing a resistance element in an embodiment. FIG. 4 is a graph showing the relationship between boron concentration and resistivity in p-type diamond produced by a production method in an embodiment. FIG. 5 is a diagram showing the results of a circuit simulation. FIG. 6 is a diagram showing the configuration of a semiconductor device. FIG. 7 is a diagram showing a diamond wafer.

[0016] In all the drawings for explaining the embodiments, the same components are generally designated by the same reference numerals, and repeated explanations thereof will be omitted. In addition, hatching may be used even in plan views to make the drawings easier to understand.

[0017] <Usefulness of diamond as a semiconductor material> For example, in the fields of future mobile communications, satellite communications, or ultra-small radar, semiconductor devices capable of high-power and high-frequency transmission are required.In this regard, semiconductor materials such as silicon (Si) and gallium arsenide (GaAs) reach their power density limits at frequencies above several GHz.For this reason, wide bandgap semiconductor materials such as silicon carbide (SiC), gallium nitride (GaN) and diamond are being considered for use in semiconductor devices.In particular, diamond has the highest thermal conductivity of all materials (four times that of SiC, 16 times that of GaN) and the highest breakdown field strength of all semiconductor materials (three times that of SiC, 10 times that of GaN).In addition, the hole mobility and hole saturation velocity in diamond are equivalent to the electron mobility and electron saturation velocity in silicon.

[0018] Diamond has excellent heat dissipation properties due to its high thermal conductivity. Therefore, by using diamond in a semiconductor device, heat generation in the semiconductor device can be suppressed and high-temperature operation of the semiconductor device can be expected. Furthermore, the high dielectric breakdown field strength of diamond makes the semiconductor device less likely to be destroyed even when high voltage is applied. For this reason, semiconductor devices using diamond are suitable for high-power applications. Furthermore, the high carrier mobility of diamond suggests that diamond has great potential as a semiconductor device for high-frequency applications.

[0019] For these reasons, diamond as a semiconductor material is considered promising for realizing next-generation semiconductor devices capable of high-power and high-frequency operation.

[0020] <Necessity of Resistor Element> As mentioned above, diamond has very excellent physical properties. For this reason, expectations are high for semiconductor devices using diamond. For example, if the performance of a voltage amplifier, which is the basis of electronic or electric circuits, can be improved by using diamond, the performance of semiconductor devices with a wide range of applications can be improved. Therefore, it is important to realize a voltage amplifier with excellent performance using diamond.

[0021] FIG. 1 is a circuit diagram of a voltage amplifier 10. In particular, FIG. 1 illustrates a common-source circuit, which is a typical example of a voltage amplifier circuit. As shown in FIG. 1, the voltage amplifier 10 has a load resistance element 1 and a field-effect transistor 2. This field-effect transistor 2 is connected in series with the load resistance element 1. The field-effect transistor 2 also has a gate G, a source S, and a drain D. The drain D is connected to the load resistance element 1. An input voltage is input between the source S and the gate G. Meanwhile, an output voltage is output from the connection node between the drain D and the load resistance element 1. Here, the voltage and current each consist of a DC component and a signal component (AC component). Specifically, in FIG. 1, the DC component (input voltage V ｉｎ , DC current I Ｄ , output voltage V ｏｕｔ ) and the signal component (input voltage v ｉｎ , alternating current i ｄ , output voltage v ｏｕｔ ) are listed separately.

[0022] In this manner, the voltage amplifier 10 is configured.

[0023] In the voltage amplifier 10, an input voltage input between the gate G and the source S is amplified and output as an output voltage from the connection node between the drain D and the load resistance element 1.

[0024] Here, the amplification factor (voltage gain) of the voltage amplifier 10 shown in FIG. ｖ=v ｏｕｔ / v ｉｎ = -g ｍ R Ｌ It can be expressed as: ｍ " indicates the mutual conductance. Ｌ " indicates the resistance value of the load resistance element 1. Therefore, in order to improve the amplification factor, the mutual conductance or the resistance value of the load resistance element 1 may be increased.

[0025] A voltage amplifier is composed of a load resistor element and a field-effect transistor. Therefore, in order to realize a voltage amplifier using diamond, not only must the field-effect transistor be composed of a diamond transistor, but the load resistor element must also be composed of diamond. In particular, since the load resistor element is conductive, it must be composed of diamond into which conductive impurities have been introduced.

[0026] Therefore, in this embodiment, attention is paid to the resistance element, which is represented by the load resistance element of the voltage amplifier.In particular, since the resistance element needs to have conductivity, in this embodiment, attention is paid to forming the resistance element from diamond into which conductive impurities are introduced.

[0027] <The difficulty of producing n-type diamond> As mentioned above, diamond is a wide band gap semiconductor material.It is considered that by introducing n-type impurities called donor into diamond, n-type diamond can be produced.Specifically, it is considered that by supplying electrons from the donor level of donor to the conduction band of diamond, n-type diamond can be realized.

[0028] Here, nitrogen can be mentioned as donor.In diamond, the donor level of nitrogen is not near the conduction band, but exists in the "deep level" away from the conduction band.Specifically, the donor level of nitrogen exists at the energy position 1.7 eV lower than the conduction band of diamond.This means that in diamond, the activation energy for exciting electrons from the donor level of nitrogen to the conduction band of diamond becomes large.

[0029] For this reason, even if nitrogen, which acts as a donor, is introduced into diamond, it is difficult to increase the number of electrons supplied to the conduction band. As a result, it is difficult to make the nitrogen-introduced diamond function as an n-type diamond.

[0030] On the other hand, it is thought that p-type diamond can be produced by introducing p-type impurities called acceptors into diamond.Specifically, it is thought that by exciting electrons from the valence band of diamond to the acceptor level of acceptor, holes are generated in the valence band of diamond, and p-type diamond can be realized.

[0031] Here, boron can be mentioned as an acceptor. The acceptor level of this boron exists near the valence band of diamond. Specifically, boron, which is an acceptor, forms an acceptor level at an energy position 0.37 eV higher than the valence band of diamond. In other words, in diamond, the acceptor level of boron does not constitute a "deep level" like the donor level of nitrogen. For this reason, the activation energy for exciting electrons from the valence band of diamond to the acceptor level of boron is not so large. As a result, it is easier to produce p-type diamond in diamond than to produce n-type diamond. For this reason, in this embodiment, the resistor element using p-type diamond will be mainly described.

[0032] <Current status of p-type diamond> For example, p-type diamond is used in diamond transistors. In detail, p-type diamond is used as a p-type contact layer interposed between the source electrode and the diamond layer or between the drain electrode and the diamond layer. That is, the p-type contact layer has the function of forming an ohmic contact between the source electrode and the diamond layer or an ohmic contact between the drain electrode and the diamond layer. For this reason, the p-type contact layer is required to have a low resistance value. Therefore, p-type diamond with a high concentration of p-type impurities introduced is used for the p-type contact layer.

[0033] This p-type diamond is formed, for example, using the hot filament CVD (Chemical Vapor Deposition) method. The hot filament CVD method is the following method. First, a metal filament such as tungsten (W) or tantalum (Ta) is energized. Then, it is heated to 2000°C or higher and 2200°C or lower. This decomposes the reactive gas and carrier gas with thermal energy, allowing diamond to grow on the substrate.

[0034] In the hot filament CVD method, the substrate is placed a few mm from the metal filament. The diamond growth rate is approximately 0.5 μm / h to 5 μm / h. The hot filament CVD method has the advantage of being capable of mass production. On the other hand, the hot filament CVD method has the disadvantage that it is difficult to accurately control the impurity concentration of the p-type impurity introduced into the diamond.

[0035] In this regard, the p-type contact layer described above only needs to achieve ohmic contact. In other words, the p-type contact layer does not need to precisely control the concentration of the p-type impurities introduced. In other words, the p-type contact layer only needs to have low resistance. Therefore, there is no problem in forming the p-type diamond constituting the p-type contact layer using the hot filament CVD method. As such, current p-type diamonds are not used in applications that require precise control of the concentration of the p-type impurities introduced. This is because the hot filament CVD method used to manufacture p-type diamonds is not suitable for accurately controlling the impurity concentration of p-type impurities. Therefore, the use of current p-type diamonds is limited to applications that do not require precise control of the impurity concentration, such as p-type contact layers.

[0036] <Necessity for Fine Control of Impurity Concentration> From the above, in order to expand the uses of p-type diamond, it is necessary to establish a method for finely controlling the concentration of p-type impurities introduced into diamond.

[0037] A more specific explanation will be given. For example, the voltage amplifier 10 shown in FIG. 1 is used in an analog circuit. In an analog circuit, it is important to know by what factor the input signal is amplified. That is, the voltage amplifier 10 constituting the analog circuit is required to have an amplification factor within an allowable range with respect to a reference value. This is because, for example, if the amplification factor of an analog circuit including the voltage amplifier 10 does not fall within an allowable range with respect to a reference value, the analog circuit may not operate normally.

[0038] In this respect, analog circuits differ from digital circuits. For example, in digital circuits, signal fluctuations (amplitude fluctuations) that do not exceed the threshold value that determines the boundary between "1" and "0" do not cause operational problems. In other words, digital circuits have a wide tolerance for deviations from a reference value. In contrast, analog circuits have a narrow tolerance for deviations from a reference value. As a result, even slight deviations from the reference value in analog circuits are likely to cause abnormal operation, such as malfunctions or malfunctions. For this reason, circuit elements used in analog circuits must be manufactured so that their actual measured values ​​have small deviations from the reference value.

[0039] Therefore, for example, the amplification factor of the voltage amplifier 10 included in the analog circuit must also be within an allowable range relative to the reference value. Here, the amplification factor of the voltage amplifier 10 is proportional to the resistance value of the load resistance element 1. Therefore, in order for the amplification factor to fall within an allowable range relative to the reference value, the resistance value of the load resistance element 1 must fall within an allowable range relative to the reference value. And, when the load resistance element 1 is made of p-type diamond, the resistance value of the p-type diamond depends on the impurity concentration of the p-type impurity introduced into the diamond. As a result, in order for the resistance value of the load resistance element 1 to fall within an allowable range relative to the reference value, the concentration of the p-type impurity must fall within an allowable range relative to the reference value.

[0040] From the above, in order to make p-type diamond usable as resistance element, it is necessary to be able to precisely control the concentration of p-type impurity, so that the concentration of p-type impurity is within the allowable range of reference value.In this respect, the method of producing current p-type diamond cannot precisely control the concentration of p-type impurity.Therefore, in order to expand the use of p-type diamond to resistance element, it is desired to establish the method of precisely controlling the concentration of p-type impurity that is introduced into diamond.

[0041] Therefore, in this embodiment, in order to realize a resistance element using p-type diamond, a device is devised to precisely control the concentration of p-type impurities introduced into diamond. The technical idea of ​​this device in this embodiment will be explained below.

[0042] <Basic Concept of the Embodiment> The basic concept of the present embodiment is to provide a method for precisely controlling the impurity concentration of diamond into which conductive impurities have been introduced, by using the following steps.

[0043] Specifically, Figure 2 is a flowchart showing the process flow for realizing the basic concept. In Figure 2, the basic concept is to first prepare a diamond substrate (S101). Next, the top surface of the diamond substrate is polished (S102). After that, polishing defects formed by polishing the top surface of the diamond substrate are removed (S103). Then, the top surface of the diamond substrate is cleaned (S104). Next, a diamond doped with conductive impurities is formed on the top surface of the diamond substrate (S105). At this time, in the step of forming the diamond doped with conductive impurities, the diamond doped with conductive impurities is formed by a plasma CVD method while feedback-controlling the temperature and controlling the amount of doped conductive impurities.

[0044] According to this basic concept, the impurity concentration of the diamond into which the conductive impurities have been introduced can be precisely controlled so that the concentration of the conductive impurities falls within an allowable range relative to the reference value. As a result, according to this basic concept, the applications of the diamond into which the conductive impurities have been introduced can be expanded.

[0045] The following describes embodiments that embody the basic concept described above.

[0046] <Embodiments> <<Configuration of Resistance Element>> FIG. 3 is a diagram showing a resistance element 100 in an embodiment.

[0047] 3, an undoped layer 102 is provided on a nitrogen-doped diamond substrate 101. For example, the top surface of the undoped layer 102 is the (001) plane.

[0048] Here, a diamond substrate 101 into which nitrogen has been introduced is used, but the present invention is not limited to this, and may be configured, for example, to manufacture a resistance element 100 on a free-standing film made of an undoped layer 102. Herein, the diamond substrate 101 and the undoped layer 102 may be collectively referred to as a diamond substrate in some cases. Also, in some cases where there is no diamond substrate 101 and the undoped layer 102 exists as a free-standing film, the term "diamond substrate" may be used in this specification. In other words, the term "diamond substrate" used in this specification is used to include the diamond substrate 101 alone, the combination of the diamond substrate 101 and the undoped layer 102, and the undoped layer 102 alone.

[0049] The non-doped layer 102 may be configured to have an off-angle of several degrees (for example, 3 degrees) in the <110> direction with respect to the (001) plane.

[0050] Here, the non-doped layer 102 referred to in this specification is a diamond layer in which the nitrogen impurity concentration is 10%, which is the lower limit of detection by a measuring device using SIMS (Secondary Ion Mass Spectrometry). １６ / cm ３ Diamond layer having a thickness of less than 100 nm.

[0051] 3, a p-type diamond 103 is formed on the non-doped layer 102. The p-type diamond 103 is made of diamond doped with boron as a p-type impurity, for example. This p-type diamond 103 is a component of the resistor element 100.

[0052] Resistance element 100 has electrodes 104 and 105 formed so as to be in contact with p-type diamond 103. The electrode material of electrodes 104 and 105 is made of, for example, gold (Au), ruthenium (Ru), aluminum (Al), titanium (Ti), molybdenum (Mo), copper (Cu), chromium (Cr), lead (Pb), zinc (Zn), platinum (Pt), or a combination thereof (such as Ti / Mo / Au).

[0053] In this manner, the resistance element 100 in the embodied embodiment is configured.

[0054] <<Method for Manufacturing Resistor Element>> In the embodiment, a method for forming a resistor element 100 made of diamond doped with p-type impurities will be described based on the basic concept.

[0055] The steps illustrated in the flowchart of FIG. 2 will now be described in detail.

[0056] 1. Step (S101) of preparing a diamond substrate: For example, the upper surface of the prepared diamond substrate is a (001) plane. This is because, from the viewpoint of improving flatness, in order to grow a high-quality film on the upper surface of the diamond substrate by CVD, the (001) plane is excellent. Furthermore, from the viewpoint of forming a high-quality film by CVD, the diamond substrate may have an off-angle of several degrees. In the embodiment, an off-angle of 3 degrees is given to the (001) plane in the <110> direction.

[0057] By providing an off-angle, the number of steps can be increased. As a result, growth species flowing on the surface can easily reach the edge of the steps. This promotes step-flow growth and suppresses the occurrence of abnormal growth.

[0058] 2. Polishing step (S102) After preparing the diamond substrate, the upper surface of the diamond substrate is polished so that the surface roughness of the upper surface is 1 nm or less. This makes it easier to uniformly apply the plasma to the upper surface of the diamond substrate. As a result, it is possible to suppress variations in the amount of p-type impurities introduced across the entire upper surface of the diamond substrate. For example, chemical mechanical polishing (CMP) can be used as a polishing method.

[0059] 3. Polishing Defect Removal Step (S103) When the upper surface of the diamond substrate is polished, polishing defects are formed on the upper surface. Therefore, the polishing defects are removed, for example, by ion beam etching (IBE). In this way, the polishing defects are removed before forming p-type diamond on the upper surface of the diamond substrate. This can reduce the change in resistance value caused by the polishing defects.

[0060] 4. Cleaning step (S104) After the above-mentioned polishing defect removal step is performed, the top surface of the diamond substrate is cleaned. This cleaning step is performed, for example, by strong acid cleaning in a clean room to remove organic and inorganic substances adhering to the top surface of the diamond substrate. This makes it possible to suppress abnormal growth that occurs in various parts of the diamond substrate when forming p-type diamond. As a result, it is possible to suppress variations in the amount of p-type impurities introduced across the entire top surface of the diamond substrate.

[0061] 5. P-type diamond formation step (S105) Next, p-type diamond 103 is formed on the upper surface of the diamond substrate. The p-type diamond 103 is formed by microwave plasma CVD rather than hot filament CVD. This allows for precise control of conditions. Therefore, the impurity concentration of the diamond doped with p-type impurities can be precisely controlled. In other words, by using microwave plasma CVD, it is possible to overcome the disadvantage of hot filament CVD, which is that it is difficult to accurately control the impurity concentration of p-type impurities. In this embodiment, boron is used as the p-type impurity introduced into the p-type diamond 103.

[0062] The above-mentioned detailed condition control includes, for example, (1) temperature control and (2) impurity introduction amount control, which are described below.

[0063] Temperature control can be achieved, for example, by carrying out the following steps. First, a radiation thermometer is used to measure the temperature during the formation of the p-type diamond 103. Then, the temperature is feedback-controlled in real time so that it falls within a range of ±5% from the target formation temperature. This temperature control can reduce temperature variations during the formation of the p-type diamond 103.

[0064] The amount of introduced impurity can be controlled by, for example, the following process: A high-quality boron source gas is introduced while being controlled by a high-precision mass flow meter. This reduces the variation in the concentration of introduced boron.

[0065] In the embodiment, the source gas for introducing boron is, for example, trimethylboron (B(CH ３ ) ３ ) is used. The boron (B) / carbon (C) ratio in the synthesis gas is adjusted to, for example, about 1.5% to 1.6%. However, the adjustment conditions vary depending on the synthesis environment, such as the apparatus used and the temperature, and the above adjustment conditions are merely an example.

[0066] In this embodiment, the microwave plasma CVD method is used in the p-type diamond formation process, and temperature and impurity introduction amount are controlled. As a result, the temperature variation when forming the p-type diamond 103 and the variation in the concentration of introduced boron can be reduced. This allows for precise control of the impurity concentration of the diamond into which boron has been introduced. For example, the boron concentration can be controlled to fall within an allowable range relative to a reference value.

[0067] In the embodiment, a test region where only p-type diamond is formed is provided on the diamond substrate. This makes it possible to confirm in advance whether the p-type diamond 103 actually has a resistance value that falls within an allowable range relative to the reference value before manufacturing the semiconductor device. Therefore, if the resistance value of the p-type diamond 103 exceeds the allowable range, it is possible to suppress the subsequent manufacturing of unnecessary semiconductor devices. Therefore, manufacturing of defective products is prevented. As a result, the manufacturing yield of semiconductor devices can be improved.

[0068] <<Characteristics of Resistor Element>> The resistor element 100 manufactured as described above has boron-doped p-type diamond 103. According to the embodiment, the impurity concentration of the boron-doped diamond can be precisely controlled. As a result, in the resistor element 100 having boron-doped p-type diamond 103, the boron concentration can be set to a concentration that falls within an allowable range with respect to a reference value.

[0069] For example, by adopting the manufacturing method of the resistance element 100 in the embodied embodiment, the concentration of boron becomes a concentration of 20% or more and 200% or less of the reference value. Here, the percentage expression of the reference value is calculated by, for example, "100 x B / A" when the reference value is "A" and the target concentration is "B". As a specific example, when the reference value A is "1 x 10 ２０ (1 / cm ３ ) and target concentration B is set to "2.0 x 10 １９ (1 / cm ３ ) ), then the target concentration B is "100 x 2.0 x 10 １９ / 1 x 10 ２０ = 20%." Also, the reference value A can be expressed as "1 x 10 ２０ (1 / cm ３ ) and the target concentration C is set to "2.0 × 10 ２０ (1 / cm ３ )), then the target concentration C is "100 x 2.0 x 10 ２０ / 1 x 10 ２０ = 200%".

[0070] The boron concentration can be controlled by adjusting the amount of boron introduced and the conditions for forming (synthesizing) the p-type diamond 103. Therefore, for example, the boron concentration can be set to 30% or more and 150% or less of the reference value. Furthermore, by making fine adjustments, the boron concentration can be set to 50% or more and 110% or less of the reference value.

[0071] The resistance value of resistor 100 having boron-doped p-type diamond 103 depends on the boron concentration. Therefore, the resistance value of resistor 100 manufactured in the embodiment can be specified based on the relationship with the boron concentration. Figure 4 is a graph showing the relationship between boron concentration and resistivity in p-type diamond 103 manufactured by the manufacturing method in the embodiment.

[0072] 4, as the boron concentration increases, the resistivity of the p-type diamond 103 decreases. Specifically, according to the research and investigation of the present inventors, when x is the boron concentration and y is the resistivity, y=10 ４３．７５６ ×x －２．２０１ The relation is 5 x 10 １８ ≦x≦1×10 ２１ It is known that this holds true within the range

[0073] As described above, according to the embodiment, the boron concentration can be set to a concentration that falls within an allowable range relative to the reference value. As a result, the resistance value of the resistor element 100, which has a relationship with the boron concentration, can also be set to a resistance value that falls within an allowable range relative to the reference value. For example, by adopting the manufacturing method of the resistor element 100 according to the embodiment, the resistance value of the resistor element can be set to 50% or more and 900% or less relative to the reference value. Here, the percentage representation relative to the reference value can be calculated by, for example, "100 x B / A" when the reference value is "A" and the target concentration is "B". As a specific example, when the reference value A is "5.45 x 10 －１ (Ωcm)" and the target concentration B is "2.73 × 10 －１ (Ωcm)”, then the target concentration B is “100×5.45×10 －１ / 2.73 x 10 －１ = 50%." Furthermore, the reference value A can be expressed as "5.45 × 10 －１(Ωcm)" and the target concentration C is "4.91 × 10 ０ (Ωcm)", the target concentration C is "100 × 4.91 × 10 ０ / 5.45 x 10 －１ = 900%".

[0074] By adjusting the amount of boron introduced and the conditions for forming (synthesizing) the p-type diamond 103, the resistance value of the resistor element 100 can be set to 80% or more and 400% or less of the reference value. Furthermore, by making fine adjustments, the resistance value of the resistor element 100 can be set to 90% or more and 200% or less of the reference value.

[0075] In this manner, the resistance element 100 in the embodied embodiment has a resistance value that is small in deviation from the reference value. The gain of the voltage amplifier is proportional to the resistance value of the resistance element. Therefore, by using this resistance element 100 in a voltage amplifier, an gain that is small in deviation from the reference value can be obtained. In other words, by using the resistance element 100 having p-type diamond 103 with a precisely controlled boron concentration in a voltage amplifier, the voltage amplifier has an gain that is close to the reference value.

[0076] For example, by employing the resistance element 100 manufactured by the manufacturing method of the embodiment as a component of a voltage amplifier, the gain of the voltage amplifier can be set to 0.1 to 10 times the reference value. Then, by adjusting the manufacturing conditions of the p-type diamond 103 that constitutes the resistance element 100, the gain of a voltage amplifier using this resistance element 100 can be set to 0.2 to 5 times the reference value. Furthermore, by making fine adjustments, the gain of the voltage amplifier can be set to 0.5 to 2 times the reference value. In this way, according to the embodiment, a voltage amplifier having a gain with a small deviation from the reference value can be realized.

[0077] From the above, there is a relationship between the boron concentration, resistance value, and amplification factor. Next, a procedure for determining the amplification factor of a voltage amplifier from the boron concentration will be described using FIG. 4. For example, when the boron concentration is set to "1.85×10" by the manufacturing method in the embodied embodiment, ２０ / cm ３In this case, if the film thickness of the p-type diamond is 1 μm, the resistance value is 1.41 kΩ / □, as shown in FIG. 4. If the resistor element has a length L / width W of 7.16, a resistor element with a resistance value of about 10 kΩ can be fabricated.

[0078] Consider a power amplifier consisting of this resistor element and a diamond transistor with a transconductance of 1 mS. The gain of this voltage amplifier is 10 times, considering that gain = - transconductance x resistance. In this way, the gain of the voltage amplifier can be determined from the boron concentration. That is, once the boron concentration is preset, the gain is determined based on the relationship between boron concentration and resistivity shown in Figure 4, the structural parameters of the resistor element (thickness, length, width), and the transconductance of the diamond transistor (known).

[0079] Conversely, if the amplification factor is preset, the set amplification factor and the known transconductance are substituted into "amplification factor = - transconductance × resistance value." This allows the resistance value to be calculated. Next, the resistivity is calculated from the resistance value. Then, based on Figure 4, the boron concentration can be determined from the calculated resistivity. In this way, the boron concentration can be determined from the amplification factor. In other words, once the amplification factor is preset, the boron concentration is determined based on the relationship between boron concentration and resistivity shown in Figure 4, the structural parameters of the resistor element (thickness, length, width), and the transconductance of the diamond transistor (known).

[0080] By utilizing the above-described procedure, for example, when an allowable range for a reference value of the amplification factor is given, it is possible to calculate an allowable range of the boron concentration for realizing an amplification factor within this allowable range. Therefore, Figure 4 can be used to associate the allowable range of the amplification factor with the allowable range of the boron concentration. In other words, Figure 4 has the extremely important technical significance of associating the allowable range of the amplification factor with the allowable range of the boron concentration.

[0081] <<Verification of Effect>> According to the embodiment, the concentration of boron introduced into p-type diamond can be precisely controlled. As a result, in a resistance element having p-type diamond, the deviation of the resistance value from the reference value is reduced. As a result, the deviation of the amplification factor of a voltage amplifier using a resistance element from the reference value is also reduced. Below, we will explain the verification results that by manufacturing a resistance element having p-type diamond using the manufacturing method in the embodiment, the deviation of the amplification factor of a voltage amplifier using a resistance element from the reference value is reduced.

[0082] The manufacturing method in the embodied embodiment allows the boron concentration to be "1.85 x 10 ２０ / cm ３ When the thickness of the p-type diamond 103 is 1 μm, the resistance value of the p-type diamond is 1.41 kΩ / □ with good reproducibility.

[0083] Here, the resistance value of p-type diamond is measured using the four-probe method using a Kyowa Riken "K-89PS." The four-probe method is a measurement method described below. First, four needle electrodes (four-probe) are placed in a straight line on the sample. Then, a constant current is passed between the two outer probes. After that, the resistance of the sample is measured by measuring the potential difference generated between the two inner probes.

[0084] Next, the shape of the resistor element is designed so that the resistance value of the resistor element having the p-type diamond described above is "10 kΩ". In this way, a resistor element with a resistance value of "10 kΩ" is designed. In addition, a diamond transistor with a mutual conductance of "1 mS" is designed. The resistor element and diamond transistor designed in this way are fabricated on a diamond substrate. This allows the creation of a voltage amplifier.

[0085] Specifically, a power amplifier with a reference gain of "10 times" is fabricated on a diamond substrate. This power amplifier is composed of a resistor element having p-type diamond and a diamond transistor. The gain of a power amplifier is expressed as "-transconductance x resistance value". For this reason, a diamond transistor with a transconductance of "1 mS" and a resistor element made of p-type diamond with a resistance value of "10 kΩ" are fabricated on the diamond substrate. Here, the parameter measurement device is as follows:

[0086] (A) Prober: Vector Semiconductor Manual Prober (TS150) (B) Semiconductor Parameter Analyzer: Keysight B1505A Next, a circuit simulation was performed on the fabricated voltage amplifier. The software used for the circuit simulation was "Excel" and "LT spice."

[0087] FIG. 5 is a diagram showing the results of the circuit simulation.

[0088] As shown in Figure 5, the signal strength of the output signal is approximately "10 times" the signal strength of the input signal. This indicates that the gain of the fabricated voltage amplifier is approximately the same as the reference value. This proves that the gain of a voltage amplifier using a resistance element fabricated by the manufacturing method of the embodied embodiment has a small deviation from the reference value.

[0089] <<Application Example>> By adopting the manufacturing method of p-type diamond in the embodied embodiment, it is possible to manufacture a resistance element having a resistance value with a small deviation from a reference value. Therefore, when this resistance element is used in a voltage amplifier, the gain of the voltage amplifier has a small deviation from the reference value. In other words, according to the embodied embodiment, it is possible to provide a voltage amplifier with excellent performance, having a gain close to the reference value.

[0090] In this regard, voltage amplifiers are the basis of electronic or electrical circuits. Therefore, if the performance of voltage amplifiers can be improved, the performance of semiconductor devices for a wide range of applications can be improved. Furthermore, semiconductor devices including voltage amplifiers are used in a variety of electronic devices. Therefore, electronic devices that include the semiconductor device in the embodied embodiment as a component can have improved performance.

[0091] In the following, application examples to electronic devices including semiconductor devices in embodied embodiments will be described.

[0092] (1) Application to optical sensor systems Optical sensor systems are used, for example, to detect the fluorescence of chemical substances. In detecting the fluorescence of chemical substances, it is important to know whether or not the substance is present. On the other hand, the amplification factor of an optical sensor system is allowed to have a certain degree of error from the reference value in terms of system configuration.

[0093] For example, the amplification factor of a voltage amplifier included in an optical sensor system is allowed to be 0.1 times or more and 10 times or less with respect to a reference value. In this case, as described above, the allowable range of the amplification factor and the allowable range of the boron concentration are related to each other. Specifically, when the reference value of the boron concentration is set to "1.0 x 10", ２０ (1 / cm ３ ) and using the formula shown in FIG. 4, in order for the amplification rate to fall within the allowable range of 0.1 times or more and 10 times or less from the reference value, the boron concentration must be within the reference value ("1.0 × 10 ２０ (1 / cm ３ )) to "3.52 x 10 １９ (1 / cm ３ ) or more "2.85 x 10 ２０ (1 / cm ３ ) or less. Therefore, the deviation from the reference value is within the range of "6.48 x 10 １９ (1 / cm ３ ) or more "1.85 x 10 ２０ (1 / cm ３ ) or less. In other words, the deviation range described above must be within the reference value of "1.0 × 10 ２０ (1 / cm ３ ) the boron concentration must be between 65% and 185% of the standard value.

[0094] When this is expressed in terms of the resistance value of the resistive element, the reference value is "5.45 x 10 －１ (Ωcm)", the allowable resistance is 2.72 × 10 －１ (Ωcm) or more 4.88 x 10 ０ (Ωcm) or less. In other words, the allowable resistance value is expressed as 50% or more and 896% or less. An optical sensor system having a voltage amplifier with such performance can be realized in the embodied mode. Therefore, the semiconductor device in the embodied mode can be applied to an optical sensor system. This makes it possible to realize a high-performance optical sensor system.

[0095] (2) Application to Semiconductor Devices for Digital Circuits For example, in semiconductor devices for digital circuits, such as logic ICs, it is important that signals do not exceed a certain threshold value. In this regard, in semiconductor devices for digital circuits, the threshold value is set to a level that will not be exceeded even if noise is superimposed on the signal. Therefore, for example, in semiconductor devices for digital circuits, even if the signal fluctuates from 0.2 to 5 times the reference value, this does not pose an operational problem. In other words, in semiconductor devices for digital circuits, an error of approximately 0.2 to 5 times the reference value is acceptable.

[0096] As described above, the allowable range of the amplification factor and the allowable range of the boron concentration are related to each other. ２０ (1 / cm ３ ) and using the formula shown in FIG. 4, in order for the amplification rate to fall within the allowable range of 0.2 times or more and 5 times or less from the reference value, the deviation of the boron concentration from the reference value is "5.17 × 10 １９ (1 / cm ３ ) or more "1.08 x 10 ２０ (1 / cm ３ ) or less. In other words, the deviation range described above must be within the reference value of "1.0 × 10 ２０ (1 / cm ３ ) the boron concentration must be 52% or more and 108% or less of the standard value.

[0097] When this is expressed in terms of the resistance value of the resistive element, the reference value is "5.45 x 10－１ (Ωcm)", the allowable resistance is 4.36×10 －１ (Ωcm) or more 2.16 x 10 ０ (Ωcm) or less. In other words, the allowable resistance value is expressed as 80% or more and 396% or less. A semiconductor device for a digital circuit having such performance can be realized in the embodied mode. Therefore, the semiconductor device in the embodied mode can be applied to a semiconductor device for a digital circuit. This makes it possible to realize a high-performance semiconductor device for a digital circuit.

[0098] (3) Application to Audio Equipment For example, it is assumed that the final volume output from an audio device will be adjusted by the user. Therefore, deviations in the gain are not a problem as long as they do not adversely affect the audio device. Specifically, the deviation range of the gain that does not adversely affect the audio device can be 0.5 to 2 times the reference value.

[0099] As described above, the allowable range of the amplification factor and the allowable range of the boron concentration are related to each other. ２０ (1 / cm ３ ) and using the formula shown in FIG. 4, in order for the amplification rate to fall within the allowable range of 0.5 to 2 times the reference value, the deviation of the boron concentration from the reference value is 2.67 × 10 １９ (1 / cm ３ ) or more "3.70 x 10 １９ (1 / cm ３ ) or less. In other words, the deviation range described above must be within the reference value of "1.0 × 10 ２０ (1 / cm ３ ) the boron concentration must be between 27% and 37% of the standard value.

[0100] When this is expressed in terms of the resistance value of the resistive element, the reference value is "5.45 x 10 －１ (Ωcm)", the allowable resistance is 4.90×10 －１ (Ωcm) or more 5.34 x 10 －１(Ωcm) or less. In other words, the allowable resistance value is expressed as 90% or more and 96% or less. Audio equipment having such performance can be realized in the embodied mode. Therefore, the semiconductor device in the embodied mode can be applied to audio equipment. This makes it possible to realize high-performance audio equipment.

[0101] <Features of the semiconductor device> According to the above-mentioned embodiment, a resistance element having a resistance value with a small deviation from a reference value can be formed from p-type diamond. Therefore, a diamond transistor and a resistance element having p-type diamond can be formed on the same diamond substrate. That is, the semiconductor device comprises a resistance element formed on the diamond substrate and a field effect transistor formed on the diamond substrate. The resistance element is made of diamond doped with conductive impurities. The field effect transistor is made of a diamond transistor. There are features in the configuration of such a semiconductor device.

[0102] FIG. 6 is a diagram showing the configuration of a semiconductor device.

[0103] In Fig. 6, the semiconductor device has a diamond transistor formation region in which a diamond transistor 200 is formed, and a resistor element formation region in which a resistor element 100 is formed. Note that the configuration of the resistor element 100 formed in the resistor element formation region is the same as in Fig. 3, so a description of the configuration of the resistor element will be omitted. Below, the configuration of the diamond transistor 200 formed in the diamond transistor formation region will be described.

[0104] Here, a surface conduction FET will be described as an example of the diamond transistor 200. However, the diamond transistor 200 is not limited to a surface conduction FET and can be configured from various types of transistors.

[0105] 6, a contact layer 201 and a contact layer 202 are provided separately from each other on the non-doped layer 102. Each of the contact layers 201 and 202 is a p-type layer in which, for example, boron, which is a p-type impurity (acceptor), is introduced at a high concentration.＋ Specifically, a high concentration of boron is introduced into each of the contact layers 201 and 202 so as to form ohmic contact with the non-doped layer 102. Specifically, the concentration of boron is, for example, 5×10 １９ / cm ３ That's it, 1 x 10 ２２ / cm ３ The thickness of each of the contact layer 201 and the contact layer 202 is, for example, about 20 nm or more and 300 nm or less.

[0106] It should be noted that the contact layer 201 and the contact layer 202 do not necessarily need to be provided, and for example, a source electrode and a drain electrode made of a gold electrode or the like may be formed directly on the hydrogen-terminated non-doped layer 102 to establish ohmic contact.

[0107] A source electrode 203 is provided on the contact layer 201. Meanwhile, a drain electrode 204 is provided on the contact layer 202. Subsequently, an insulating film 205 is provided on the non-doped layer 102 between the contact layer 201 and the contact layer 202, and a gate electrode 206 is provided on this insulating film 205.

[0108] The electrode materials of the source electrode 203, the drain electrode 204, and the gate electrode 206 are, for example, gold (Au), ruthenium (Ru), aluminum (Al), titanium (Ti), molybdenum (Mo), copper (Cu), chromium (Cr), lead (Pb), zinc (Zn), platinum (Pt), or a combination thereof (e.g., Ti / Mo / Au). The thickness of each of the source electrode 203, the drain electrode 204, and the gate electrode 206 is, for example, about 10 nm or more and 500 nm or less.

[0109] On the other hand, the insulating film 205 is, for example, an aluminum oxide film (Al ２ O ３ ), silicon oxide film (SiO ２ ), calcium fluoride film (CaF ２ ), hafnium oxide film (HfO ２), aluminum nitride film (AlN), boron nitride film (BN), silicon nitride film (Si ３ N ４ ), silicon oxynitride film (SiON), tantalum oxide film (Ta ２ O ５ ), titanium oxide film (TiO ２ ), tungsten oxide film (WO ３ ), lanthanum fluoride film (LaF ３ ), or magnesium fluoride film (MgF ２ ) The insulating film 205 has a thickness of, for example, about 5 nm to 1000 nm. When manufacturing a fine surface conduction FET, it is desirable that the insulating film 205 have a thickness of 100 nm or less.

[0110] In this manner, a semiconductor device is constructed in which the diamond transistor 200 and the resistance element 100 are formed on the diamond substrate.

[0111] The advantages of the semiconductor device will be described below.

[0112] For example, with conventional techniques, it is difficult to precisely control the concentration of p-type impurities introduced into the p-type diamond 103. This makes it difficult to keep the resistance value within an allowable range relative to a reference value. This makes it difficult to form a resistance element having the p-type diamond 103.

[0113] For this reason, in the current technology, a semiconductor device including a voltage amplifier is composed of a combination of a component in which a diamond transistor is formed on a diamond substrate and a component in which a resistor element is formed on a silicon substrate, for example. In other words, a semiconductor device including a voltage amplifier is composed of a combination of multiple discrete components.

[0114] Current semiconductor devices configured as described above have room for improvement, as follows: The multiple discrete components are connected to each other by wires such as gold wires. This causes noise due to the parasitic inductance of the wires. Furthermore, because the semiconductor device is composed of multiple discrete components, it is difficult to miniaturize the semiconductor device. Furthermore, the increase in wiring and electrode pads results in increased parasitic resistance and parasitic capacitance. This causes signal delays. Therefore, it is difficult to realize a semiconductor device for high-frequency signals. Furthermore, the process of manufacturing the semiconductor device becomes complicated. This leads to a decrease in the manufacturing yield of the semiconductor device and an increase in manufacturing costs.

[0115] Furthermore, semiconductor devices including voltage amplifiers are composed of multiple discrete components. For example, each time a semiconductor device including a voltage amplifier with a different gain is manufactured, a custom-made resistor element must be manufactured for the diamond transistor. This is unrealistic considering practical implementation.

[0116] In contrast, in the semiconductor device of this embodiment, for example, as shown in FIG. 6, a diamond transistor 200 and a resistance element 100 are formed on a diamond substrate. Therefore, according to this embodiment, a semiconductor device including a voltage amplifier can be constructed from a single component. In other words, in this embodiment, a semiconductor device including a voltage amplifier is not constructed from multiple discrete components. Therefore, according to this embodiment, the above-mentioned room for improvement (disadvantages) that arise when constructed from multiple discrete components does not become apparent. In other words, according to the semiconductor device of this embodiment, performance can be improved. Furthermore, the diamond transistor 200 and the resistance element 100 formed on the diamond substrate can be integrally covered with a passivation film (surface protection film). This makes it possible to suppress performance changes of the semiconductor device over time. Furthermore, the process of combining multiple discrete components is also unnecessary. In other words, according to this embodiment, the manufacturing process can be simplified. Therefore, the manufacturing yield of semiconductor devices can be improved. This leads to a reduction in manufacturing costs.

[0117] As described above, according to this embodiment, the diamond transistor 200 and the resistance element 100 can be formed on the diamond substrate.

[0118] Furthermore, by developing this configuration, for example, as shown in Figure 7, in a diamond wafer WF having a plurality of chip regions CR, a configuration can be realized in which a resistance element 100 having diamond introduced with conductive impurities and a diamond transistor 200 are formed in each of the plurality of chip regions CR. In this way, in a configuration in which a plurality of types of diamond elements D1 (resistance element 100 and diamond transistor 200) are formed in each of the plurality of chip regions CR of the diamond wafer WF, the performance of the diamond element D1 is more stable than a combination of a plurality of discrete parts.

[0119] In addition, when a large number of diamond elements D1 are formed on the diamond wafer WF, it becomes easier to manufacture diamond elements D1 with uniform performance. For this reason, the configuration in which a large number of diamond elements D1 are formed on the diamond wafer WF has great practical advantages.

[0120] Furthermore, even if "unevenness" occurs in the physical property values ​​of the diamond elements D1 formed on the diamond wafer WF, the "unevenness" in the physical property values ​​may be compensated for. In other words, in a diamond wafer WF having a plurality of chip regions CR, even if the physical property values ​​of diamond differ between a first region and a second region of the plurality of chip regions CR, the characteristics of the semiconductor device based on the difference in the physical property values ​​may be compensated for.

[0121] For example, if the resistance value becomes high in a "certain region" of the diamond wafer WF, the performance of the diamond transistor 200 will deteriorate (transconductance will decrease). On the other hand, in this case, the resistance value of the resistance element 100 may become large. As a result, for example, in a voltage amplifier composed of the diamond transistor 200 and the resistance element 100, the amplification factor (= -transconductance x resistance value) does not change significantly. In other words, depending on the type of diamond element D1 formed on the diamond wafer WF, the "unevenness" of the local physical property values ​​of the diamond wafer WF may be compensated for.

[0122] In this way, in a diamond wafer WF having multiple chip regions CR, it is useful to form a resistor element 100 having diamond with conductive impurities introduced therein and a diamond transistor 200 in each of the multiple chip regions CR.

[0123] <Regarding Reference Values> Finally, the reference values ​​referred to in this specification will be described.

[0124] The reference value in this specification refers to a design value. This design value can be specified, for example, by a product circuit diagram or product specifications. Here, if the design value cannot be specified by a circuit diagram or product specifications, the reference value refers to an average value calculated by the following procedure. Specifically, (1) ten semiconductor devices are prepared. (2) Actual measurements are obtained for each semiconductor device, and the average of the ten actual measurements is taken as the average value.

[0125] For example, to obtain an average resistance value of a resistor element, the resistance values ​​of the resistor elements included in ten semiconductor devices are measured to obtain ten actual measured values. The average value obtained in this manner serves as a secondary reference value when the design value cannot be identified.

[0126] As described above, the reference value in this specification is primarily a design value, but when the design value cannot be specified, it is secondarily an average value calculated by the above-mentioned procedure. As a result, the reference value in this specification is clearly defined.

[0127] The invention made by the inventor has been specifically described above based on the embodiments thereof, but it goes without saying that the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the invention.

[0128] REFERENCE SIGNS LIST 1 Load resistance element 2 Field effect transistor 100 Resistor element 101 Diamond substrate 102 Non-doped layer 103 p-type diamond 104 Electrode 105 Electrode 200 Diamond transistor 201 Contact layer 202 Contact layer 203 Source electrode 204 Drain electrode 205 Insulating film 206 Gate electrode CR Chip region D Drain D1 Diamond element G Gate S Source WF Diamond wafer

Claims

1. A semiconductor device including a resistor element having diamond doped with conductive impurities, the resistance value of the resistor element being 50% or more and 900% or less of a reference value.

2. A semiconductor device according to claim 1, wherein the resistance value of the resistive element is 80% or more and 400% or less of the reference value.

3. A semiconductor device according to claim 1, wherein the resistance value of the resistor element is 90% or more and 200% or less of the reference value.

4. A semiconductor device according to claim 1, wherein the conductive impurity is a p-type impurity.

5. A semiconductor device including a resistor element having diamond doped with conductive impurities, wherein the concentration of the conductive impurities is 20% or more and 200% or less with respect to a reference value.

6. A semiconductor device according to claim 5, wherein the concentration of the conductive impurity is 30% or more and 150% or less of the reference value.

7. A semiconductor device according to claim 5, wherein the concentration of the conductive impurity is 50% or more and 110% or less of the reference value.

8. A semiconductor device according to claim 5, wherein the conductive impurity is boron.

9. A semiconductor device including a voltage amplifier, the voltage amplifier having a load resistance element and a transistor connected in series with the load resistance element, the load resistance element having diamond doped with a conductive impurity, and the transistor being a diamond transistor.

10. A semiconductor device according to claim 9, wherein the amplification factor of the voltage amplifier is 0.1 to 10 times the reference value.

11. A semiconductor device according to claim 9, wherein the amplification factor of the voltage amplifier is 0.2 to 5 times the reference value.

12. A semiconductor device according to claim 9, wherein the amplification factor of the voltage amplifier is 0.5 to 2 times the reference value.

13. A semiconductor device comprising: a resistor element formed on a diamond substrate; and a transistor formed on the diamond substrate, wherein the resistor element has diamond doped with a conductive impurity, and the transistor is a diamond transistor.

14. A semiconductor device according to claim 13, wherein the resistor element and the transistor are components of a voltage amplifier.

15. A semiconductor device according to claim 13, wherein the conductive impurity is a p-type impurity.

16. A diamond wafer having a plurality of chip regions, each of the plurality of chip regions having formed therein at least a resistor element having diamond doped with a conductive impurity, and a transistor constituted by a diamond transistor.

17. A diamond wafer as described in claim 16, wherein the plurality of chip regions include a first region and a second region, and the physical properties of diamond in the first region and the second region are different.

18. A diamond wafer as described in claim 17, wherein the resistive element and the transistor are components of a voltage amplifier, the physical property is a resistance value, the mutual conductance of the transistor formed in the first region is smaller than the mutual conductance of the transistor formed in the second region, and the resistance value of the resistive element formed in the first region is higher than the resistance value of the resistive element formed in the second region.

19. An electronic device comprising a semiconductor device according to any one of claims 1 to 15 as a component.

20. A method for manufacturing a semiconductor device, comprising: (a) preparing a diamond substrate; (b) polishing the upper surface of the diamond substrate; (c) removing polishing defects; (d) cleaning the upper surface of the diamond substrate; and (e) forming a diamond doped with conductive impurities on the upper surface of the diamond substrate, wherein in the step (e), the diamond doped with conductive impurities is formed by a plasma CVD method while feedback-controlling the temperature and controlling the amount of the conductive impurities introduced.

21. A method for manufacturing a semiconductor device according to claim 20, wherein the conductive impurity is a p-type impurity.

22. A method for manufacturing a semiconductor device as defined in claim 20, wherein the diamond substrate is a diamond wafer having a plurality of chip regions, and in step (e), a resistive element having at least the diamond doped with the conductive impurity is formed in each of the plurality of chip regions.

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