Solid secondary battery

Abstract

To provide an all-solid secondary battery having higher safety than a conventional lithium ion secondary battery using an electrolytic solution, specifically, a thin film type solid secondary battery, and to provide a method of manufacturing the same.SOLUTION: A mixed material obtained by co-evaporation of SiO and an organic complex of lithium is used as a solid electrolyte. That is, a solid electrolyte layer formed using a mixed material of an inorganic material and an organic material is used for the solid secondary battery. The ratio of oxygen to silicon in the solid electrolyte layer is greater than 1 and less than 2.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] One aspect of the present invention relates to an article, a method, or a manufacturing method. Alternatively, the present invention relates to a process, Pertaining to a machine, manufacture, or composition of matter. One embodiment of the present invention is a semiconductor device, a display device, a light-emitting device, a power storage device, a lighting device, or an electronic device. The present invention relates to a device or a method for manufacturing the same.

[0002] In this specification, the term "electronic device" refers to any device having a power storage device. Electro-optical devices having a power storage device, and information terminal devices having a power storage device are all electronic devices. [Background technology]

[0003] 2. Description of the Related Art Electronic devices that are carried by users or worn by users have been actively developed.

[0004] Electronic devices carried by users or worn by users are primary energy storage devices, which are examples of power storage devices. It operates on batteries or secondary batteries. Electronic devices carried by users are designed to be used for long periods of time. It is desirable to use a large-capacity secondary battery for this purpose. If a battery is built in, the problem is that a large-capacity secondary battery is large and heavy. Development is underway to develop small or thin, high-capacity secondary batteries that can be built into electronic devices.

[0005] A liquid such as an organic solvent is used as a medium for moving the lithium ions, which are carrier ions. However, secondary batteries that use liquids are widely used. In this case, since a liquid is used, there is a problem of decomposition reaction of the electrolyte depending on the temperature range and potential used. In addition, secondary batteries that use liquid electrolytes have the problem of leakage. There is a risk of fire due to

[0006] Fuel cells are secondary batteries that do not use liquids, but they use precious metals for the electrodes and solid electrolyte materials. It is also an expensive device.

[0007] In addition, there are electric storage devices called solid-state batteries that use solid electrolytes as secondary batteries that do not use liquids. For example, Patent Document 1 and Patent Document 2 are disclosed. 3. The electrolyte of the lithium ion secondary battery is either a solvent, a gel, or a solid electrolyte. It is stated that it is used.

[0008] Patent Document 1 describes a method for forming a lithium cobalt oxide film on a positive electrode current collector by sputtering. Examples of this are given. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] U.S. Patent No. 8,404,001 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-023032 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-229308 Summary of the Invention [Problem to be solved by the invention]

[0010] All-solid-state secondary batteries, which are safer than conventional lithium-ion secondary batteries that use electrolytes, are Specifically, the present invention provides a thin-film solid-state secondary battery (also called a thin-film all-solid-state battery) and a method for manufacturing the same.

[0011] Another problem is to provide a new material as a solid electrolyte for a thin-film solid secondary battery. This is one of them.

[0012] Another problem is to provide an all-solid-state secondary battery suitable as a secondary battery for thin electronic devices such as card terminals. This is also one of the problems.

[0013] Another problem is to provide an all-solid-state secondary battery suitable as a secondary battery for wearable devices, specifically small electronic devices in the form of wristwatches, and for small electronic devices in the form of glasses. This is also one of the problems. Especially in wearable devices, since they may come into contact with the user's skin, it is desired to use an all-solid-state secondary battery with high safety that does not cause liquid leakage or the like.

Means for Solving the Problems

[0014] One of the configurations disclosed in this specification uses a mixed material obtained by co-evaporation of SiO X (0 < X < 2) and an organic complex of lithium. That is, it is one of the features of the present invention to use a solid electrolyte layer made of a mixed material of an inorganic material and an organic material in a solid secondary battery.

[0015] SiO X (0 < X < 2) The material to be co-evaporated with can be any of a simple substance of an alkali metal or an alkaline earth metal, an organic complex, or a compound. For example, Li, Li2O, etc. can be mentioned. In particular, an organic complex of lithium is preferable, and among them, 8-hydroxyquinolinato-lithium (abbreviation: Liq) is preferable.

[0016] On the positive electrode active material layer or the negative electrode active material layer, an organic complex of lithium and SiO X(0 < X < 2) is co-evaporated to form a solid electrolyte layer. This is a method for manufacturing a solid secondary battery.

[0017] In the above manufacturing method, since the positive electrode and the negative electrode are formed by sputtering, it is preferable that the positive electrode active material layer or the negative electrode active material layer is formed by sputtering. The sputtering apparatus can also perform continuous film formation using the same chamber or multiple chambers, and can be a multi-chamber type manufacturing apparatus or an inline type manufacturing apparatus. The sputtering method is a manufacturing method suitable for mass production using a chamber and a sputtering target. Also, the sputtering method can form thin films and has excellent film formation characteristics.

[0018] Moreover, it is not particularly limited to the sputtering method, and the positive electrode active material layer or the negative electrode active material layer can also use a vapor phase method (vacuum evaporation method, spraying method, pulsed laser deposition method (PLD method), ion plating method, coaxial dusp spraying method, aerosol deposition method). Note that the aerosol deposition (AD) method is a method of forming a film without heating the substrate. An aerosol refers to fine particles dispersed in a gas.

[0019] Also, the positive electrode, the negative electrode, the positive electrode active material layer, or the negative electrode active material layer may be formed by using the CVD method or the ALD (Atomic layer Deposition) method.

[0020] Also, a solid secondary battery can be manufactured by laminating the material films obtained by the above manufacturing method.

[0021] The obtained solid secondary battery is also one of the present inventions, and its configuration includes a positive electrode, a negative electrode, and a solid electrolyte layer having silicon, oxygen, lithium, and carbon between the positive electrode and the negative electrode.

[0022] In the above-mentioned structure, the solid electrolyte layer further contains nitrogen. This nitrogen is a lithium organic complex. This is due to the nitrogen in the body.

[0023] In the above-mentioned configuration, a negative electrode active material layer containing silicon is provided between the negative electrode and the solid electrolyte layer. The negative electrode active material layer is formed using a sputtering target whose main component is silicon. It is possible.

[0024] In the above-described structure, a positive electrode active material layer is provided between the positive electrode and the solid electrolyte layer. The porous layer is made of a sputtering target whose main component is lithium cobalt oxide (LiCoO2). The film can be formed using a nozzle.

[0025] The silicon to oxygen ratio (O / Si) of the solid electrolyte layer is greater than 1 and less than 2. That is, The ratio of oxygen to silicon in the solid electrolyte layer is greater than 1 and less than 2. By enclosing the solid electrolyte in this way, lithium ions can be easily diffused and the solid electrolyte does not have electronic conductivity. It can be realized.

[0026] In order to improve the lithium ion conductivity of the solid electrolyte, phosphorus or the like may be added. stomach.

[0027] In this specification, the oxygen ratio of the solid electrolyte layer is based on the value obtained by EDX measurement. To do so.

[0028] Among EDX measurements, ED is a method of measuring while scanning an area and evaluating the area two-dimensionally. It is sometimes called EDX area analysis. Data on linear areas can be extracted from EDX area analysis and used to Evaluating the distribution of the molecular concentration within the positive electrode active material particles is sometimes called line analysis.

[0029] By EDX surface analysis (for example, elemental mapping), the concentrations of silicon, nitrogen, carbon, and oxygen in the interior or surface layer can be quantitatively analyzed. Also, by EDX line analysis, the peaks of the concentrations of silicon, nitrogen, carbon, and oxygen can be analyzed. The unit of the EDX concentration is, for example, atomic %.

Advantages of the Invention

[0030]

[0031] X A thin film obtained by co-evaporating an organic complex of lithium and SiO(0 < X < 2) enables the production of a thin-film type solid secondary battery.

[0032] Since no electrolyte solution is used, the thin-film type solid secondary battery has heat resistance such that it can be used even at high temperatures.

[0033] Also, the thin-film type solid secondary battery can be multilayered in series or parallel connection by increasing the number of stacked layers with one set consisting of a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer, thereby increasing the capacity.

[0034]

[0035] Also, the capacity of the thin-film type solid secondary battery can be increased by increasing the area. [Figure 1] [Figure 2] [[ID=e46]]Moreover, by using the peeling and transfer technique, it can be folded into a desired size after increasing the area.

Brief Description of the Drawings

[0035] [Figure 1] FIG. 1 is a cross-sectional view showing one aspect of the present invention. [Figure 2] FIGS. 2A and 2B are a top view and a cross-sectional view showing one aspect of the present invention. [Figure 3] FIG. 3 shows EDX data of a solid electrolyte layer showing one embodiment of the present invention. [Figure 4] FIG. 4 is a cross-sectional view showing one embodiment of the present invention. [Figure 5] FIG. 5 is a production flow diagram showing one embodiment of the present invention. [Figure 6] FIG. 6A is a perspective view showing an example of a battery cell, FIG. 6B is a perspective view of a circuit, and FIG. 6C is a perspective view of the battery cell and the circuit superimposed on each other. [Figure 7] FIG. 7A is a perspective view showing an example of a battery cell, FIG. 7B is a perspective view of a circuit, and FIGS. 7C and 7D are perspective views of the battery cell and the circuit superimposed on each other. [Figure 8] FIG. 8 is a diagram showing a configuration example of a semiconductor device. [Figure 9] FIG. 9 is a diagram showing a configuration example of a semiconductor device. [Figure 10] 10A, 10B, and 10C are diagrams showing configuration examples of a semiconductor device. [Figure 11] FIG. 11A is a perspective view of a battery cell, and FIG. 11B is a diagram showing an example of an electronic device. [Figure 12] 12A, 12B, and 12C are diagrams showing examples of electronic devices. DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following description, and various modifications in form and details are possible by those skilled in the art. Furthermore, the present invention should not be construed as being limited to the description of the following embodiments. It is not something that can be done.

[0037] (Embodiment 1) FIG. 1 shows an embodiment in the case of a single-layer cell of a thin-film solid secondary battery. In this specification, a single-layer cell of a solid secondary battery is a cell that is made up of a positive electrode, a solid electrode, a The term "anode" refers to a set of units having at least an electrolyte layer and a negative electrode.

[0038] The single-layer cell shown in FIG. 1 has a positive electrode 201, a positive electrode active material layer 204, a solid electrolyte layer 205, and a 202, the negative electrode active material layer 205, and the negative electrode 203 are laminated in this order. The drawing shows only a portion of the electrodes, and the electrodes are arranged so that the planar area of ​​the positive electrode is smaller than the planar area of ​​the negative electrode. The ends are rounded, and only one end is shown in FIG.

[0039] The substrate 101 may be a ceramic substrate, a glass substrate, a plastic substrate, or a silicon substrate. , metal substrates, etc.

[0040] The materials for the positive electrode 201 and the negative electrode 203 include Al, Ti, Cu, Au, Cr, W, Mo, One or more conductive materials selected from Ni, Ag, etc. are used. Sputtering, vapor deposition, etc. can be used. In the sputtering method, metal By using a mask, it is possible to selectively form a film. The conductive film is patterned by selectively removing it using dry etching or wet etching. You may also use the

[0041] The positive electrode active material layer 204 is made of lithium cobalt oxide (LiCoO2, LiCo2O4, etc.). and lithium manganese oxide (LiMnO2, LiMn2O4) as the main component of sputtering targets, and lithium nickel oxide It can be formed by sputtering using oxides (Li with O2, LiNi2O4, etc.). In addition, lithium manganese cobalt oxide (LiMnCoO4, Li2MnCoO4, etc.) (d), ternary materials of nickel, cobalt, and manganese (LiNi 1 / 3 Mn 1 / 3 Co 1 / 3 O 2: NCM), ternary materials of nickel, cobalt, and aluminum (LiNi 0.8 Co 0.1 5Al 0.05 O2: NCA), etc. can also be used.

[0042] The solid electrolyte layer 202 uses a mixed material of an inorganic material and an organic material. In this embodiment, S iO X (0 < X < 2) and a mixed material obtained by co-evaporation with an organic complex of lithium are used.

[0043] SiO X (0 < X < 2) and the material to be co-evaporated can be any of a simple substance, an organic complex, or a compound of an alkali metal or an alkaline earth metal, and for example, Li, Li2O, etc. can be cited. In particular, an organic complex of lithium is preferable, and among them, 8-hydroxyquinoline lithium (abbreviation: Liq) is preferable. As other organic materials to be co-evaporated with SiO (0 < X < 2), dilithium phthalocyanine (phthalocyanine dilithium), lithium X (0 < X < 2) can also be used. 2-(2-pyridyl)phenolate (abbreviation: Lipp), lithium 2-(2’,2’ ’-bipyridin-6’-yl)phenolate (abbreviation: Libpp) ’.

[0044] Also, it is preferable to adjust the film-forming conditions so that the ratio of silicon to oxygen (O / Si) of the obtained solid electrolyte layer 202 is greater than 1 and less than 2. By setting it within such a range, it is possible to realize a solid electrolyte layer in which lithium ions diffuse easily and there is no electronic conductivity.

[0045] The solid electrolyte layer 202 may have a laminated structure. In this case, one layer contains lithium phosphate. Nitrogen-doped lithium (Li3PO4) 4-Y N Y : Also called LiPON It is also possible to stack layers (Y>0).

[0046] The negative electrode active material layer 205 is formed by sputtering or the like, using a film mainly composed of silicon or a film mainly composed of carbon. Films containing titanium oxide, vanadium oxide, indium oxide, zinc oxide, A tin film, a nickel oxide film, or the like can be used. A metal film may also be used. Lithium titanium oxide (Li4Ti5O 12 , LiTi 2O4, etc.) may also be used.

[0047] In this way, thin-film solid-state secondary batteries are made by stacking various films, which reduces the interface resistance and the internal resistance. It is also preferable to reduce the resistance. It is preferable to have an excellent combination.

[0048] The layers can be stacked in any order. An example of a different stacking order from that shown in Figure 1 is shown in Figure 2. 2A and 2B. FIG. 2A is a top view, and FIG. 2B is a cross-sectional view taken along line AA′ in FIG. 2A. It corresponds to the surface view.

[0049] As shown in FIG. 2B, a negative electrode 203 is formed on the substrate 101, and a negative electrode active material is formed on the negative electrode 203. layer 205, solid electrolyte layer 202, positive electrode active material layer 204, positive electrode 201, and protective layer 206 in this order. It is layered.

[0050] These films can be formed using a metal mask. The negative electrode 203, the negative electrode active material layer 205, the positive electrode active material layer 204, the positive electrode 201, and the protective layer 206 are Alternatively, a co-evaporation method can be used to form a solid electrolytic The solid electrolyte layer 202 is selectively formed by mixing Si powder (SiO) and Li powder. The film is formed by co-evaporating the two materials. Alternatively, an electron beam evaporation source is used. The material is not limited to Si powder (SiO), and pellet-shaped materials are also usable. You can also use something like that.

[0051] As shown in FIG. 2A, a part of the negative electrode 203 is exposed to form a negative electrode terminal. The area other than the positive electrode 201 is covered with a protective layer 206. The area other than the positive electrode terminal is covered with a protective layer 206.

[0052] The protective layer 206 is made of a silicon nitride film (also called an SiN film). The contact film is formed by sputtering.

[0053] Through the series of steps described above, the thin-film solid secondary battery shown in FIG. 2A can be manufactured.

[0054] Furthermore, EDX area analysis (e.g., element mapping) was performed on the obtained thin-film solid secondary battery. By using the above, silicon, nitrogen, carbon, etc., in the inside or surface portion of the solid electrolyte layer 202 can be removed. The concentrations of nitrogen and oxygen can be quantitatively analyzed.

[0055] The solid electrolyte layer 202 was formed and subjected to EDX measurement.

[0056] The EDX spectrum of the cross section of the solid electrolyte layer 202 will be described. The electron beam is irradiated onto the sample, and the energy and number of characteristic X-rays generated are measured. The DX spectrum was obtained. The results are shown in Figure 3. The atomic concentration (%) is also shown in Table 1.

[0057] [Table 1]

[0058] These results indicate that the obtained material is easy for lithium ions to diffuse and has good electronic conductivity. It can be said that this is an indispensable material and can be used as a solid electrolyte.

[0059] The oxygen ratio of the solid electrolyte layer can be calculated based on the value obtained by EDX measurement. The silicon to oxygen ratio (O / Si) in the electrolyte layer is greater than 1 and less than 2. By setting the range, lithium ions can be easily diffused and the solid electrolyte has no electronic conductivity. Quality can be achieved.

[0060] In addition, the deposition of solid electrolytes is not limited to co-evaporation. Gases are generated simultaneously and cooled on the same surface to form a film. It can also be done as follows.

[0061] (Embodiment 2) In embodiment 1, an example of a single-layer cell was shown, but in this embodiment, a multi-layer cell 4 and 5 show examples of the thin-film solid secondary battery in the case of a multi-layer cell. It is one of the forms.

[0062] FIG. 4 shows an example of a cross section of a three-layer cell.

[0063] A positive electrode 201 is formed on a substrate 101, and a positive electrode active material layer 204 and a solid electrolyte layer 205 are formed on the positive electrode 201. The first cell is constructed by sequentially forming a cathode active material layer 202, an anode active material layer 205, and an anode 203. is doing.

[0064] Furthermore, a second negative electrode active material layer, a second solid electrolyte layer, a second positive electrode active material layer, and a second negative electrode active material layer are formed on the negative electrode 203. The second cell is constructed by sequentially forming a material layer and a second layer of positive electrode.

[0065] Furthermore, a third layer of positive electrode active material is formed on the second layer of positive electrode, a third layer of solid electrolyte, and a third layer of negative electrode. The third cell is constructed by sequentially forming an active material layer and a third negative electrode layer.

[0066] In FIG. 4, a protective layer 206 is formed last. The three-layer stack shown in FIG. 4 has a large capacitance. To achieve this, the devices are connected in series, but they can also be connected in parallel using external wiring. In addition, series and parallel or series-parallel can be selected for external wiring.

[0067] The solid electrolyte layer 202, the second solid electrolyte layer, and the third solid electrolyte layer are made of the same material. The use of the above is preferable because it can reduce the manufacturing cost.

[0068] FIG. 5 shows an example of a manufacturing flow for obtaining the structure shown in FIG.

[0069] In Fig. 5, in order to reduce the number of manufacturing steps, an LCO film is used as the positive electrode active material layer, and A titanium film is used as the conductor and is regarded as the positive electrode. The silicon film is used as the current collector and the titanium film is used as the negative electrode. By using it as an electrode, a three-layer stacked cell can be realized with a small configuration.

[0070] (Embodiment 3) Fig. 6A is an external view of a thin-film solid secondary battery. It has a terminal 951 and a terminal 952. The terminal 951 is a positive electrode, and the terminal 952 is a negative electrode. They are electrically connected to each other.

[0071] 6B is an external view of the battery control circuit. The battery control circuit shown in FIG. A circuit 912 and an antenna 914 are provided over the substrate 900. The antenna 914 is electrically connected to the circuit 912. The circuit 912 has a terminal 971 and a terminal The circuit 912 is electrically connected to the terminal 911.

[0072] The terminal 911 is connected to, for example, a device to which power is supplied from the thin-film solid-state secondary battery. For example, it may be connected to a display device, a sensor, etc.

[0073] The layer 916 has a function of shielding an electromagnetic field generated by the secondary battery 913, for example. The layer 916 may be made of, for example, a magnetic material.

[0074] 6C shows an example in which the battery control circuit shown in FIG. 6B is disposed on the secondary battery 913. 71 is electrically connected to terminal 951, and terminal 972 is electrically connected to terminal 952. 6 is disposed between the substrate 900 and the secondary battery 913.

[0075] The substrate 900 is preferably a flexible substrate.

[0076] By using a flexible substrate as the substrate 900, a thin battery control circuit can be realized. As shown in FIG. 7D, which will be described later, the battery control circuit can be wound around the secondary battery. It is possible.

[0077] 7A is an external view of a thin-film solid secondary battery. 0 and layer 916.

[0078] As shown in FIG. 7C, the substrate 900 is bent to fit the shape of the secondary battery 913, and the battery control circuit As shown in Figure 7D, by arranging the It can be wrapped around.

[0079] (Embodiment 4) This embodiment is applicable to the battery control circuit described in the above embodiment. Specifically, we will explain the structure of transistors with different electrical characteristics. By adopting this configuration, it is possible to automatically design a semiconductor device. In addition, transistors having different electrical characteristics can be stacked. This allows the integration degree of the semiconductor device to be increased.

[0080] The semiconductor device shown in FIG. 8 includes a transistor 300, a transistor 500, a capacitor 600, and 10A is a cross-sectional view of the transistor 500 in the channel length direction, and 10B is a cross-sectional view of the transistor 500 in the channel width direction, and FIG. 10C is a cross-sectional view of the transistor 300. 00 in the channel width direction.

[0081] The transistor 500 is an OS transistor. Since the current is extremely small, by using this for a transistor included in a semiconductor device, It is possible to retain the written data voltage or charge for a long period of time. Refresh operations are infrequent or not required, so The power consumption of the semiconductor device can be reduced.

[0082] The semiconductor device described in this embodiment includes a transistor 300, a transistor The transistor 500 is located above the transistor 300. The capacitor 600 is provided above the transistor 300 and the transistor 500. are.

[0083] The transistor 300 is disposed on a substrate 311, and includes a conductor 316, an insulator 315, and a substrate 316. 11, a semiconductor region 313 serving as a source region or a drain region, It has a resistive region 314a and a low resistive region 314b.

[0084] The transistor 300 is formed by forming a top surface of the semiconductor region 313 and a channel region 314 as shown in FIG. 10C. The side surfaces in the width direction are covered with the conductor 316 via the insulator 315. By making the resistor 300 a fin type, the effective channel width is increased, and This can improve the on-characteristics of the transistor 300. In addition, the contribution of the electric field of the gate electrode can be increased, thereby improving the off-state characteristics of the transistor 300. .

[0085] The transistor 300 may be either a p-channel type or an n-channel type.

[0086] The region where the channel of the semiconductor region 313 is formed, the region nearby, the source region, or the drain region In the low resistance region 314a and the low resistance region 314b, which are the drain region, silicon is It preferably contains a semiconductor such as a silicon-based semiconductor, and preferably contains single crystal silicon. Or Ge (germanium), SiGe (silicon germanium), GaAs (gallium It may be formed of a material containing gallium aluminum arsenide (GaAlAs), GaAlAs (Gallium Aluminum Arsenide), etc. By applying stress to the crystal lattice and changing the lattice spacing, we can control the effective mass of silicon. Alternatively, GaAs and GaAlAs may be used to form a transistor. The 300 is a HEMT (High Electron Mobility Transistor) tor) can also be used.

[0087] The low resistance region 314a and the low resistance region 314b are semiconductor regions applied to the semiconductor region 313. In addition to the body material, elements that impart n-type conductivity, such as arsenic or phosphorus, or p-type conductivity, such as boron, are added. The element imparting electrical conductivity is included.

[0088] The conductor 316 that functions as the gate electrode is made of an element that gives n-type conductivity, such as arsenic or phosphorus. Semiconductor materials such as silicon that contain elements that impart p-type conductivity, such as silicon or boron A conductive material such as a metal material, an alloy material, or a metal oxide material can be used.

[0089] In addition, since the work function is determined by the conductor material, by selecting the conductor material, Specifically, the threshold voltage of the transistor can be adjusted by using titanium nitride as the conductor. It is preferable to use materials such as tantalum nitride or tantalum nitride. To achieve this, metal materials such as tungsten and aluminum are used as layers for the conductor. is preferable, and tungsten is particularly preferable in terms of heat resistance.

[0090] The transistor 300 shown in FIG. 8 is an example, and the structure is not limited to this example. An appropriate transistor may be used depending on the driving method. A unipolar circuit consisting of only n-channel transistors, etc. 9, the structure of the transistor 300 is changed to an oxide semiconductor. The transistor 500 may have the same structure as the transistor 500. Details of 0 will be given later.

[0091] Over the transistor 300 are insulators 320, 322, 324, and The bodies 326 are stacked one on top of the other.

[0092] The insulators 320, 322, 324, and 326 may be, for example, oxide. Silicon, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, oxide Aluminum oxynitride, aluminum nitride oxide, aluminum nitride, etc. may be used.

[0093] In this specification, silicon oxynitride refers to a material containing more oxygen than nitrogen as its composition. Silicon nitride oxide refers to a material that contains more nitrogen than oxygen. In this specification, aluminum oxynitride refers to a material with a large amount of aluminum. It refers to a material that contains more oxygen than nitrogen, and aluminum oxide nitride is a material with a indicates a material that contains more nitrogen than oxygen.

[0094] The insulator 322 smooths out the steps caused by the transistor 300 and other components disposed below it. For example, the top surface of the insulator 322 may have a function as a planarizing film. To improve flatness, the surface is flattened by a planarization process such as chemical mechanical polishing (CMP). It's fine.

[0095] The insulator 324 is also provided with a substrate 311 or a transistor 300 or the like. A film having a barrier property that prevents hydrogen and impurities from diffusing is used in the area where the capacitor 500 is provided. It is preferable that

[0096] An example of a film having a barrier property against hydrogen is silicon nitride formed by a CVD method. Here, a semiconductor having an oxide semiconductor such as the transistor 500 can be used. When hydrogen diffuses into the element, the characteristics of the semiconductor element may be deteriorated. A film that suppresses hydrogen diffusion is used between the transistor 500 and the transistor 300. Specifically, the film that suppresses hydrogen diffusion is a film that has a small amount of hydrogen desorption. The membrane.

[0097] The amount of desorbed hydrogen can be analyzed using, for example, thermal desorption spectroscopy (TDS). For example, the amount of hydrogen desorption from the insulator 324 can be measured by TDS analysis when the surface temperature of the film is 5 In the range of 0 to 500°C, the amount of desorption converted to hydrogen atoms is Converted to 10 x 10 15 atoms / cm 2 Less than or equal to 5 x 10 15 at oms / cm 2 The following is fine.

[0098] It is preferable that the insulator 326 has a lower dielectric constant than the insulator 324. For example, The dielectric constant of the insulator 326 is preferably less than 4, more preferably less than 3. The relative dielectric constant of the insulating material 26 is preferably 0.7 times or less than the relative dielectric constant of the insulating material 324, and more preferably 0.6 times or less. It is more preferable to use a material with a low dielectric constant as the interlayer film to reduce the parasitic capacitance that occurs between wiring. It is possible.

[0099] In addition, the insulators 320, 322, 324, and 326 have a capacitance of 600 Alternatively, the conductor 328 and the conductor 330 connected to the transistor 500 are embedded. The conductors 328 and 330 function as plugs or wiring. In addition, the conductor having the function of a plug or wiring can be used to connect multiple structures. In addition, in this specification and the like, the same reference numerals may be used to refer to wiring and devices connected to the wiring. In other words, when a part of the conductor functions as a wiring, , and a portion of the conductor may also function as a plug.

[0100] The materials for each plug and wiring (conductor 328, conductor 330, etc.) include metal materials, alloys, and the like. Conductive materials such as gold, metal nitride, or metal oxide materials are used as single or multilayered layers. High-melting materials such as tungsten and molybdenum, which have both heat resistance and electrical conductivity, can be used. It is preferable to use a point material, and it is preferable to use tungsten. It is preferable to form the wiring layer from a low-resistance conductive material such as aluminum or copper. This can reduce the wiring resistance.

[0101] A wiring layer may be provided on the insulator 326 and the conductor 330. For example, in FIG. An insulator 350, an insulator 352, and an insulator 354 are stacked in this order. In addition, a conductor 356 is formed on the insulators 350, 352, and 354. The conductor 356 functions as a plug or wiring that connects to the transistor 300. The conductor 356 is made of the same material as the conductors 328 and 330. It can be established as follows.

[0102] For example, the insulator 350 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator. In addition, the conductor 356 has a barrier property against hydrogen. It is preferable that the insulating material 350 contains a conductor. In particular, the insulating material 350 has a barrier property against hydrogen. In the opening, a conductor having a barrier property against hydrogen is formed. The transistor 300 and the transistor 500 can be separated by a barrier layer. Therefore, the diffusion of hydrogen from the resistor 300 to the transistor 500 can be suppressed.

[0103] As a conductor having a barrier property against hydrogen, for example, tantalum nitride or the like is used. In addition, by laminating tantalum nitride and highly conductive tungsten, The diffusion of hydrogen from the transistor 300 can be suppressed while maintaining the conductivity of the transistor 300. In this case, the tantalum nitride layer having a barrier property against hydrogen has a barrier property against hydrogen. It is preferable that the insulating material 350 is in contact with the insulating material 350.

[0104] A wiring layer may be provided on the insulator 354 and the conductor 356. For example, in FIG. An insulator 360, an insulator 362, and an insulator 364 are stacked in this order. In addition, a conductor 366 is formed on the insulators 360, 362, and 364. The conductor 366 functions as a plug or wiring. The conductors 328 and 330 can be formed using the same materials.

[0105] For example, the insulator 360 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator. The conductor 366 has a barrier property against hydrogen. It is preferable that the insulating material 360 contains a conductor. In particular, the insulating material 360 has a barrier property against hydrogen. In the opening, a conductor having a barrier property against hydrogen is formed. The transistor 300 and the transistor 500 can be separated by a barrier layer. Therefore, the diffusion of hydrogen from the resistor 300 to the transistor 500 can be suppressed.

[0106] A wiring layer may be provided on the insulator 364 and the conductor 366. For example, in FIG. An insulator 370, an insulator 372, and an insulator 374 are stacked in this order. In addition, a conductor 376 is formed on the insulators 370, 372, and 374. The conductor 376 functions as a plug or wiring. The conductors 328 and 330 can be formed using the same materials.

[0107] For example, the insulator 370 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator. In addition, the conductor 376 has a barrier property against hydrogen. It is preferable that the insulating material 370 contains a conductor. In particular, the insulating material 370 has a barrier property against hydrogen. In the opening, a conductor having a barrier property against hydrogen is formed. The transistor 300 and the transistor 500 can be separated by a barrier layer. Therefore, the diffusion of hydrogen from the resistor 300 to the transistor 500 can be suppressed.

[0108] A wiring layer may be provided on the insulator 374 and the conductor 376. For example, in FIG. An insulator 380, an insulator 382, ​​and an insulator 384 are stacked in this order. In addition, a conductor 386 is formed on the insulators 380, 382, ​​and 384. The conductor 386 functions as a plug or wiring. The conductors 328 and 330 can be formed using the same materials.

[0109] For example, the insulator 380 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator. The conductor 386 has a barrier property against hydrogen. It is preferable that the insulating material 380 has a barrier property against hydrogen. In the opening, a conductor having a barrier property against hydrogen is formed. The transistor 300 and the transistor 500 can be separated by a barrier layer. Therefore, the diffusion of hydrogen from the resistor 300 to the transistor 500 can be suppressed.

[0110] In the above, the wiring layer including the conductor 356, the wiring layer including the conductor 366, and the conductor 376 The wiring layer including the conductor 386 has been described above. The semiconductor device is not limited to this. Alternatively, the number of wiring layers may be three or less, or five or more wiring layers similar to the wiring layer including the conductor 356 may be provided. Good too.

[0111] On the insulator 384, an insulator 510, an insulator 512, an insulator 514, and an insulator 516 are formed. , and are stacked in this order. It is preferable that either of the insulating layers 516 is made of a material that has a barrier property against oxygen or hydrogen. stomach.

[0112] For example, the insulator 510 and the insulator 514 may include, for example, the substrate 311 or the transistor. Hydrogen and impurities are introduced from the region where the transistor 300 is provided to the region where the transistor 500 is provided. It is preferable to use a film that has a barrier property to prevent diffusion. The same materials as in 4 can be used.

[0113] As an example of a film with barrier properties against hydrogen, silicon nitride formed by CVD is used. Here, a semiconductor element including an oxide semiconductor such as the transistor 500 can be The diffusion of hydrogen may deteriorate the characteristics of the semiconductor device. A film that suppresses hydrogen diffusion is used between the transistor 500 and the transistor 300. Specifically, the film that suppresses hydrogen diffusion is a film that desorbs a small amount of hydrogen. .

[0114] In addition, as a film having a barrier property against hydrogen, for example, an insulator 510 and an insulator 5 14 uses metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide. It is preferable.

[0115] In particular, aluminum oxide is a material that can absorb oxygen and hydrogen, which can cause fluctuations in the electrical characteristics of transistors. Therefore, it has a high blocking effect that prevents impurities such as acid and moisture from passing through the membrane. Aluminum oxide is resistant to hydrogen, moisture, etc. during and after the transistor manufacturing process. It is possible to prevent impurities from being mixed into the transistor 500. This can suppress the release of oxygen from the oxide that makes up the transistor. Suitable for use as a protective film against 500.

[0116] For example, the insulators 512 and 516 may be made of the same material as the insulator 320. In addition, by using materials with a relatively low dielectric constant for these insulators, , the parasitic capacitance occurring between the wirings can be reduced. The body 516 may be a silicon oxide film, a silicon oxynitride film, or the like.

[0117] In addition, the insulators 510, 512, 514, and 516 are provided with conductors 5 18, and conductors (for example, conductor 503) that constitute the transistor 500 are embedded. The conductor 518 is connected to the capacitor 600 or the transistor 300. The conductor 518 functions as a plug or wiring. It may be provided using the same material as the body 330 .

[0118] In particular, the insulator 510 and the conductor 518 in the area in contact with the insulator 514 are free of oxygen, hydrogen, It is preferable that the conductive material has a barrier property against water. The transistor 300 and the transistor 500 have a barrier property against oxygen, hydrogen, and water. The layer separating the transistors 300 and 500 allows for the separation of hydrogen. Diffusion can be suppressed.

[0119] Above the insulator 516 is the transistor 500 .

[0120] As shown in FIGS. 10A and 10B, transistor 500 includes an insulator 514 and an insulator The conductor 503 is disposed so as to be embedded in the insulator 516, and the insulator 516 and the conductor 5 an insulator 520 disposed on the insulating layer 520; and an insulator 522 disposed on the insulating layer 520. An insulator 524 is disposed on the insulator 522, and an oxide 5 is disposed on the insulator 524. 30a, oxide 530b disposed on oxide 530a, and oxide 530b disposed on oxide 530b. Conductor 542a and conductor 542b are spaced apart from each other, and conductor 542a and conductor The conductive material 542a is disposed on the conductive material 542b, and an opening is formed between the conductive material 542a and the conductive material 542b so as to overlap the conductive material 542a. The insulating layer 580 is formed on the bottom and side of the opening, and the oxide 530c is formed on the bottom and side of the opening. The insulator 550 is disposed on the surface on which the insulating film 550 is formed. The conductor 550 is disposed on the surface on which the insulating film 550 is formed. 60 and has.

[0121] 10A and 10B, the oxide 530a, the oxide 530b, the conductor 542a and 542b, and an insulator 544 is disposed between the insulator 580. As shown in FIGS. 10A and 10B, the conductor 560 is preferably made of an insulator 560. 50, and a conductor 560a provided inside the conductor 560a. It is preferable to have a conductor 560b provided thereon. As shown in FIG. 1, an insulator 574 is disposed on top of an insulator 580, a conductor 560, and an insulator 550. It is preferable to place

[0122] In this specification and the like, oxide 530a, oxide 530b, and oxide 530c These are sometimes collectively referred to as oxide 530.

[0123] In the transistor 500, the region where the channel is formed and the vicinity thereof are oxidized. 5 shows a structure in which three layers of an oxide 530a, an oxide 530b, and an oxide 530c are stacked. However, the present invention is not limited to this. For example, a single layer of oxide 530b, an oxide a two-layer structure of oxide 530b and oxide 530a; a two-layer structure of oxide 530b and oxide 530c; Alternatively, a stacked structure of four or more layers may be provided. Although the conductor 560 is shown as a two-layer laminate structure, the present invention is not limited to this. For example, the conductor 560 may have a single layer structure or a laminated structure of three or more layers. 8 and 10A is an example, and the structure of the transistor 500 is not limited to this example. It is only necessary to use an appropriate transistor depending on the circuit configuration and driving method.

[0124] Here, the conductor 560 functions as the gate electrode of the transistor, and the conductors 542a and The conductor 542b functions as a source electrode and a drain electrode, respectively. As shown, the conductor 560 is inserted through the opening in the insulator 580 and the conductors 542a and 542b. The conductor 560, the conductor 542a, and the conductor 542b are formed so as to be embedded in the sandwiched region. The placement of the conductive material 542b is selected to be self-aligned with the opening of the insulator 580. In the transistor 500, the gate electrode is connected between the source electrode and the drain electrode. Therefore, the conductor 560 can be positioned with a margin for alignment. Since the transistor 500 can be formed without any additional steps, the area occupied by the transistor 500 can be reduced. This allows for miniaturization and high integration of semiconductor devices.

[0125] Furthermore, a conductor 560 is formed in a self-aligned manner in the region between the conductors 542a and 542b. Therefore, the conductor 560 has an overlapping area with the conductor 542a or the conductor 542b. This prevents the formation of a gap between the conductor 560 and the conductors 542a and 542b. Therefore, the parasitic capacitance of the transistor 500 can be reduced. It is possible to improve the speed and have high frequency characteristics.

[0126] Conductor 560 may function as a first gate (also called top gate) electrode. In addition, the conductor 503 may function as a second gate (also called a bottom gate) electrode. In this case, the potential applied to the conductor 503 may be different from the potential applied to the conductor 560. The threshold voltage of the transistor 500 is controlled by changing them independently without linking them together. In particular, applying a negative potential to the conductor 503 can turn on the transistor 50 By increasing the threshold voltage of 0 to be higher than 0V, it is possible to reduce the off-current. Therefore, applying a negative potential to the conductor 503 increases the potential of the conductor 560 more than when no negative potential is applied. The drain current when the applied potential is 0V can be reduced.

[0127] The conductor 503 is arranged to overlap the oxide 530 and the conductor 560. Therefore, when a potential is applied to the conductor 560 and the conductor 503, The electric field generated by the conductor 503 is connected to the electric field generated by the conductor 503, and the chalcogenide formed in the oxide 530 The chel forming area can be covered.

[0128] In this specification, a pair of gate electrodes (a first gate electrode and a second gate electrode) The structure of a transistor in which the channel formation region is electrically surrounded by the electric field of This is called a surrounded channel (S-channel) structure. In this case, the surrounded channel (S-channel) structure is The acid in contact with the conductor 542a and the conductor 542b which function as the electrode and the drain electrode The side and periphery of the oxide 530 are I-type, just like the channel forming region. In addition, the side and periphery of the oxide 530 in contact with the conductor 542a and the conductor 542b The side can be I-shaped like the channel formation region because it is in contact with the insulator 544. In this specification and the like, Type I can be treated as the same as high-purity genuine, which will be described later. The S-channel structure disclosed in this specification and the like can be a fin type structure or a planar type structure. The S-channel structure provides resistance to short channel effects. In other words, it is possible to provide a transistor in which the short channel effect is less likely to occur.

[0129] The conductor 503 has the same structure as the conductor 518, and the insulators 514 and 5 Conductor 503a is formed in contact with the inner wall of opening 16, and conductor 503b is formed further inside. In the transistor 500, the conductor 503a and the conductor 503b are Although a stacked structure is shown, the present invention is not limited to this. The electric conductor 503 may be configured as a single layer or a laminated structure of three or more layers.

[0130] Here, the conductor 503a prevents the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms. It is preferable to use a conductive material that has the function of suppressing the impurities (i.e., the impurities are less likely to permeate). Alternatively, the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) is suppressed. It is preferable to use a conductive material that has the above-mentioned function (i.e., that is difficult for oxygen to permeate). In this specification, the function of suppressing the diffusion of impurities or oxygen means the function of suppressing the diffusion of the above impurities or oxygen. The function is to suppress the diffusion of any one or all of the above oxygen.

[0131] For example, the conductor 503a has a function of suppressing the diffusion of oxygen, so that the conductor 503b This can prevent the conductivity from decreasing due to oxidation.

[0132] When the conductor 503 also functions as a wiring, the conductor 503b is made of tungsten, copper, Alternatively, it is preferable to use a highly conductive material containing aluminum as a main component. In this embodiment, the conductor 503 is illustrated as a stack of conductors 503a and 503b. However, the conductor 503 may have a single layer structure.

[0133] The insulators 520, 522, and 524 function as a second gate insulating film. It has.

[0134] Here, the insulator 524 in contact with the oxide 530 has more oxygen than the stoichiometric composition. In other words, the insulator 524 has an excess oxygen region. It is preferable that the insulator containing such excess oxygen is connected to the oxide 530. By providing the oxide 530 as a O :oxygen vacanc y), thereby improving the reliability of the transistor 500. When hydrogen enters the oxygen vacancy in the oxide 530, the defect (hereinafter referred to as V O Sometimes called H ) can act as a donor, generating electrons as carriers. Some of these may bond with oxygen, which bonds with metal atoms, to generate electrons that act as carriers. Therefore, a transistor using an oxide semiconductor containing a large amount of hydrogen has a normally-on In addition, hydrogen in the oxide semiconductor is easily degraded by stress such as heat or an electric field. Because hydrogen is easily mobile, the reliability of transistors deteriorates when a large amount of hydrogen is contained in an oxide semiconductor. In one embodiment of the present invention, V in the oxide 530 O Reduce H as much as possible It is preferable to make it highly pure or substantially highly pure. O H To obtain a sufficiently reduced oxide semiconductor, impurities such as moisture and hydrogen must be removed from the oxide semiconductor. (This may also be referred to as dehydration or dehydrogenation treatment) and supplying oxygen to the oxide semiconductor. It is important to supply oxygen to compensate for the oxygen deficiency (sometimes referred to as oxygen addition treatment). V O The oxide semiconductor in which impurities such as H are sufficiently reduced is used as the channel formation region of the transistor. By using this, stable electrical properties can be imparted.

[0135] As an insulator having an excess oxygen region, specifically, an oxide film in which some oxygen is released by heating is used. It is preferable to use a material that releases oxygen when heated. In the normal desorption spectroscopy (DDS) analysis, The calculated amount of oxygen released is 1.0 x 10 18 atoms / cm 3 More than 1.0x, preferably 10 19 atoms / cm 3 More preferably, 2.0 × 10 19atoms / cm 3 or more, or 3.0 x 10 20 atoms / cm 3 The oxide film is as described above. The surface temperature of the film during the TDS analysis was 100°C or higher and 700°C or lower, or 10 The temperature is preferably in the range of 0°C or higher and 400°C or lower.

[0136] In addition, the insulator having the excess oxygen region is brought into contact with the oxide 530 and then subjected to heat treatment. One or more of the following may be performed: microwave processing, RF processing, or the like. By this, water or hydrogen in the oxide 530 can be removed. In 30, a reaction occurs in which the VoH bond is broken, in other words, "V O H→Vo+H This reaction occurs, and some of the hydrogen generated is dehydrogenated. The oxide 530 or the insulator adjacent to the oxide 530 is removed by combining with the element to form H2O. In addition, some of the hydrogen may be gettered to the conductor 542.

[0137] The microwave treatment may be carried out using, for example, an apparatus having a power source that generates high-density plasma. Alternatively, it is preferable to use a device having a power source that applies RF to the substrate side. By using a gas containing oxygen and high density plasma, high density oxygen radicals are generated. By applying RF to the substrate side, the high density plasma generated Oxygen radicals are efficiently introduced into the oxide 530 or into the insulator near the oxide 530. The microwave treatment can be carried out at a pressure of 133 Pa or more, preferably 200 The microwave treatment may be performed at a pressure of 400 Pa or more, more preferably 400 Pa or more. The gases introduced into the device are, for example, oxygen and argon, with an oxygen flow rate ratio (O / (O2+Ar)) is set to 50% or less, preferably 10% or more and 30% or less.

[0138] In addition, during the manufacturing process of the transistor 500, the surface of the oxide 530 is exposed. The heat treatment is preferably carried out at a temperature of, for example, 100° C. or higher and 450° C. or lower. The heat treatment is preferably performed at a temperature of 350° C. or higher and 400° C. or lower. Or in an inert gas atmosphere, or oxidizing gas is 10 ppm or more, 1% or more, or For example, it is preferable to carry out the heat treatment in an oxygen atmosphere. This supplies oxygen to the oxide 530, and oxygen vacancies (V O ) can be reduced. The heat treatment may be carried out under reduced pressure. Alternatively, the heat treatment may be carried out under nitrogen gas or nitrogen gas. After heat treatment in an active gas atmosphere, oxidizing gas was added at 10p to compensate for the oxygen that was released. The treatment may be carried out in an atmosphere containing at least pm, at least 1%, or at least 10% of an oxidizing gas. After heat treatment in an atmosphere containing 10 ppm or more, 1% or more, or 10% or more, Alternatively, the heat treatment may be performed in a nitrogen gas or inert gas atmosphere.

[0139] In addition, by performing an oxygen addition treatment on the oxide 530, oxygen vacancies in the oxide 530 are filled with oxygen. In other words, it promotes the reaction "Vo + O → null" Furthermore, the supplied oxygen reacts with the hydrogen remaining in the oxide 530. This allows the hydrogen to be removed as H2O (dehydration). The hydrogen remaining in the substance 530 recombines with the oxygen vacancy to form V. Oinhibits the formation of H It is possible.

[0140] Also, if the insulator 524 has an excess oxygen region, the insulator 522 may be oxygen-resistant (e.g., It has the function of suppressing the diffusion of oxygen (element atoms, oxygen molecules, etc.) (the oxygen mentioned above is less likely to permeate) is preferred.

[0141] The insulator 522 has a function of suppressing the diffusion of oxygen and impurities, and the oxide 530 is effective. The oxygen does not diffuse to the insulator 520 side, which is preferable. This can prevent the insulator 524 and the oxide 530 from reacting with oxygen.

[0142] The insulator 522 may be, for example, aluminum oxide, hafnium oxide, aluminum and hafnium oxide. oxides containing ammonium (hafnium aluminate), tantalum oxide, zirconium oxide, titanium Lead zirconate titanate (PZT), strontium titanate (SrTiO3), or (B Insulators containing so-called high-k materials such as a,Sr)TiO3 (BST) are deposited as single layers or As transistors become smaller and more highly integrated, Thinning the gate insulating film can cause problems such as leakage current. By using high-k materials as insulators that function as a transistor, the physical thickness can be maintained. This makes it possible to reduce the gate potential during start operation.

[0143] In particular, it has the function of suppressing the diffusion of impurities and oxygen (the oxygen is difficult to penetrate) ) Insulators containing oxides of one or both of aluminum and hafnium, which are insulating materials It is recommended to use an insulator containing oxides of either or both aluminum and hafnium. , aluminum oxide, hafnium oxide, oxides containing aluminum and hafnium (hafnium It is preferable to use such a material as the insulator 5. When the insulator 522 is formed, the insulator 522 prevents oxygen from being released from the oxide 530 and prevents the transistor from being formed. It functions as a layer that suppresses the intrusion of impurities such as hydrogen from the periphery of 500 into the oxide 530. .

[0144] Alternatively, for example, aluminum oxide, bismuth oxide, or germanium oxide may be added to these insulators. Niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, Alternatively, zirconium oxide may be added to these insulators, or these insulators may be nitrided. Silicon oxide, silicon oxynitride, or silicon nitride may be stacked on the insulator.

[0145] The insulator 520 is preferably thermally stable. For example, silicon oxide and Silicon oxide nitride and silicon oxynitride are suitable because they are thermally stable. By combining the insulator with silicon oxide or silicon oxynitride, thermally stable and It is possible to obtain an insulator 520 having a laminated structure with a high relative dielectric constant.

[0146] The transistor 500 has an oxide 530 including a channel formation region, which functions as an oxide semiconductor. For example, the oxide 530 may be an In-Mn-Zn oxide. n oxides (element M is aluminum, gallium, yttrium, copper, vanadium, beryllium Smoke, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum Tungsten, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium It is preferable to use a metal oxide such as one or more selected from the following. The In-M-Zn oxide that can be applied as 30 is CAAC-OS (c-axis ali annealed crystalline oxide semiconductor Alternatively, CAC-OS (Cloud-Aligned Compositing System) It is preferable that the material is a tetraoxide semiconductor. C represents an example of a crystal structure, and CAC represents an example of a function or material configuration. The material 530 may be an In-Ga oxide or an In-Zn oxide.

[0147] CAC-OS is a material that has a conductive function in some parts and an insulating function in other parts. The material as a whole functions as a semiconductor. When ethanolic oxide is used in the active layer of a transistor, the conductive function is The insulating function is to allow the electrons (or holes) that become carriers to flow. The conductive function and insulating function work in a complementary manner. By doing so, the switching function (On / Off function) is set to CAC-OS or CAC -metal oxide. CAC-OS or CAC-meta By separating the functions of each compound, we can maximize the functions of both compounds. It can be done.

[0148] In addition, CAC-OS or CAC-metal oxide has a conductive region and an insulating region. The conductive region has the above-mentioned conductive function, and the insulating region has the above-mentioned insulating function. In addition, the conductive region and the insulating region are formed at the nanoparticle level in the material. The conductive and insulating regions may be separated by a thin film. In addition, the conductive area may be observed as a cloud-like connected area with a blurred periphery. This may be the case.

[0149] In addition, in the CAC-OS or CAC-metal oxide, a conductive region and an insulating region are The peripheral region is 0.5 nm to 10 nm, preferably 0.5 nm to 3 nm. The following sizes may be dispersed in the material:

[0150] In addition, CAC-OS and CAC-metal oxide have different band gaps. For example, CAC-OS or CAC-metal oxide e is a component with a wide gap due to the insulating region and a narrow gap due to the conductive region. In this configuration, when a carrier is flowed, In the component with a narrow gap, carriers mainly flow. The component having a narrow gap acts complementary to the component having a wide gap. Carriers also flow to the wide gap component in conjunction with the CA component. C-OS or CAC-metal oxide is used for the channel formation region of the transistor. When the transistor is turned on, the transistor has a high current driving capability, i.e., a large on-state current. High field effect mobility can be obtained.

[0151] That is, CAC-OS or CAC-metal oxide is a matrix composite material. (matrix composite), or metal matrix composite It can also be called atrix composite.

[0152] Note that metal oxides that function as oxide semiconductors include single-crystal oxide semiconductors and other non-crystalline oxide semiconductors. As a non-single-crystal oxide semiconductor, for example, CAA C-OS, polycrystalline oxide semiconductor, nc-OS (nanocrystalline oxide de semiconductor), pseudo-amorphous oxide semiconductor (a-like OS: amorphous-like oxide semiconductor), and non crystalline oxide semiconductors.

[0153] IGZO can be broadly divided into Amorphous and Crystalline They are classified into amorphous and crystal. Crystal Among the ine, CAAC (c-axis aligned crystalline) , nc (nanocrystalline), and CAC (Cloud-Aligned) Composite) is included in the classification of Crystalline. gle crystal, poly crystal, and completely am Orphous is excluded. Also, among Crystals, there is a single crystal. Al, and poly crystal.

[0154] CAAC-OS has a c-axis orientation and multiple nanocrystals are connected in the ab-plane direction. The crystal structure has distortion. The distortion is the area where multiple nanocrystals are connected. In the region, the lattice arrangement is changed between a region with a uniform lattice arrangement and another region with a uniform lattice arrangement. Indicates the point where the direction is changing.

[0155] Nanocrystals are basically hexagonal, but they are not limited to regular hexagonal shapes and may be non-regular hexagonal. The distortion may also have lattice arrangements such as pentagons and heptagons. In CAAC-OS, clear grain boundaries (grain boundaries) are observed even near the strain. It is difficult to confirm the crystal structure due to the distortion of the lattice arrangement. This is because the CAAC-OS is aligned in the ab-plane direction. In this case, the arrangement of oxygen atoms is not dense, and the bond distance between atoms is reduced by the substitution of metal elements. This is because distortion can be tolerated by changing the

[0156] In addition, the CAAC-OS has a layer containing indium and oxygen (hereinafter referred to as an In layer) and an element A layered crystal structure in which layers containing M, zinc, and oxygen (hereinafter referred to as (M, Zn) layers) are stacked. It is noted that indium and element M tend to have a layered structure. It is possible, and when the element M in the (M,Zn) layer is replaced with indium, (In,M,Zn) Also, when indium in the In layer is replaced with element M, (In,M ) layer.

[0157] CAAC-OS is a metal oxide with high crystallinity. Since it is difficult to identify grain boundaries, the decrease in electron mobility caused by grain boundaries is unlikely to occur. In addition, the crystallinity of metal oxides can be reduced by the incorporation of impurities or the generation of defects. Therefore, CAAC-OS is a metal oxide with few impurities and defects (such as oxygen vacancies). Therefore, the physical properties of the metal oxide having the CAAC-OS are stable. Therefore, metal oxides having CAAC-OS are heat-resistant and highly reliable.

[0158] nc-OS is a material that can be used in microscopic areas (e.g., areas between 1 nm and 10 nm, especially areas between 1 nm and 3 nm). The nc-OS has periodic atomic arrangement in the nanometer range (nm or less). There is no regularity in the crystal orientation between the crystals. Therefore, no orientation is observed throughout the film. Therefore, depending on the analysis method, nc-OS may be distinguished from a-like OS or amorphous oxide semiconductor. It may be difficult to distinguish between the two.

[0159] In addition, In-G, a type of metal oxide containing indium, gallium, and zinc, a-Zn oxide (also known as "IGZO") has a stable structure when made into the above-mentioned nanocrystals. In particular, IGZO tends to have difficulty growing crystals in the atmosphere, so Small crystals (e.g., crystals of several mm or several cm) are more difficult to measure than large crystals (here, crystals of several mm or several cm). In some cases, the structure may be more stable if the material is made into a nanocrystal (as described above).

[0160] The a-like OS is a metal oxide semiconductor with a structure between the nc-OS and amorphous oxide semiconductor. A-like OS has voids or low density areas. e-OS has lower crystallinity than nc-OS and CAAC-OS.

[0161] Oxide semiconductors (metal oxides) have a variety of structures, each with different properties. The oxide semiconductor of one embodiment of the present invention is an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-lik The crystalline structure may have two or more of e-OS, nc-OS, and CAAC-OS.

[0162] In addition, it is preferable to use a metal oxide with a low carrier concentration for the transistor 500. When the carrier concentration of the metal oxide is reduced, the impurity concentration in the metal oxide is reduced. In this specification and the like, the impurity concentration is low and the defect level density is low. The low level density is called high purity intrinsic or substantially high purity intrinsic. Impurities include, for example, hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, and nickel. , silicon, etc.

[0163] In particular, hydrogen contained in metal oxides reacts with oxygen that bonds with metal atoms to form water, Oxygen vacancies may be formed in the metal oxide. If defects are present, the transistor may have normally-on characteristics. The defect where hydrogen has entered the oxygen vacancy acts as a donor, and electrons, which act as carriers, are generated. In addition, some of the hydrogen atoms bond with oxygen atoms that bond with metal atoms, and the electrons that are carriers Therefore, transistors using metal oxides containing a large amount of hydrogen The capacitor tends to have normally-on characteristics.

[0164] The defect where hydrogen has entered the oxygen vacancy can function as a donor for the metal oxide. It is difficult to quantitatively evaluate the defects. Therefore, in this specification, the metal oxide As a parameter of the oxide, the capacitance of the capacitor, which is assumed to be in a state where no electric field is applied, is used instead of the donor concentration. In other words, the "carrier concentration" described in this specification and the like is the "donor concentration." This can sometimes be rephrased as "concentration."

[0165] Therefore, when a metal oxide is used as the oxide 530, the hydrogen in the metal oxide is reduced as much as possible. Specifically, it is preferable that metal oxides are analyzed by secondary ion mass spectrometry ( SIMS (Secondary Ion Mass Spectrometry) The resulting hydrogen concentration is 1×10 20 atoms / cm 3 Less than 1 x 10 19 a toms / cm 3 less than 5 × 10 18 atoms / cm 3 Less than or even better Preferably 1 x 10 18 atoms / cm 3 Impurities such as hydrogen are sufficiently reduced. By using this metal oxide in the channel formation region of a transistor, stable electrical characteristics can be achieved. It can be granted.

[0166] In addition, when a metal oxide is used for the oxide 530, the carrier of the metal oxide in the channel formation region The concentration is 1 x 10 18 cm -3 Preferably, it is 1×10 or less. 17 cm -3 less than More preferably, it is 1×10 16 cm -3 More preferably, it is less than 1 x10 13 cm -3 More preferably, it is less than 1×10 12 cm -3 is less than It is more preferable that the lower limit of the carrier concentration of the metal oxide in the channel formation region is There is no particular limitation, but for example, 1 × 10 -9 cm -3 It can be said that:

[0167] When a metal oxide is used for the oxide 530, the conductor 542 (the conductor 542a and When the conductor 542b) comes into contact with the oxide 530, the oxygen in the oxide 530 is transferred to the conductor 54 2, the conductor 542 may be oxidized. It is highly likely that the conductivity of the conductor 542 will decrease. The diffusion of oxygen into the oxide 530 can be expressed as the absorption of oxygen by the conductor 542. can be done.

[0168] Furthermore, oxygen in the oxide 530 is converted into conductors 542 (conductors 542a and 542b). Diffusion into the oxide 530b and the conductor 542a. A foreign layer may be formed between the oxide 530b and the conductor 542. Since the hetero layer contains a large amount of oxygen, it is presumed that the hetero layer has insulating properties. The three-layer structure of the oxide 530b and the different layer is a three-layer structure consisting of a metal, an insulator, and a semiconductor. It can be considered as MIS (Metal-Insulator-Semiconductor) structure. It is sometimes called a diode junction structure, or a MIS structure. do.

[0169] The different layer is not limited to being formed between the conductor 542 and the oxide 530b. For example, a different layer may be formed between the conductor 542 and the oxide 530c, or between the conductor 54 2 and oxide 530b, and between conductor 542 and oxide 530c. There is a match.

[0170] In addition, the metal oxide that functions as a channel formation region in the oxide 530 is a band gap. It is preferable to use a material with a gap of 2 eV or more, preferably 2.5 eV or more. As shown in Fig. 1, by using a metal oxide with a wide band gap, the off-state current of a transistor can be reduced. can be reduced.

[0171] The oxide 530 has the oxide 530a under the oxide 530b, so that the oxide 530 is thicker than the oxide 530a. This can suppress the diffusion of impurities from the structure formed below into the oxide 530b. In addition, by having the oxide 530c on the oxide 530b, the oxide 530c can be formed more efficiently than the oxide 530c. It is possible to suppress the diffusion of impurities from the structure formed above into the oxide 530b. .

[0172] The oxide 530 has a laminated structure of a plurality of oxide layers each having a different atomic ratio of each metal atom. Specifically, in the metal oxide used for the oxide 530a, the constituent elements are preferably The atomic ratio of element M in the oxide 530b is It is preferable that the atomic ratio of the metal oxide used for the oxide 530a is larger than that of the element M. In the oxide 530b, the atomic ratio of the element M to In is It is preferable that the atomic ratio of element M to In is larger than that of element M. In the metal oxide used, the atomic ratio of In to the element M is It is preferable that the atomic ratio of In to the element M in the metal oxide is larger than that of In. Oxide 530c is a metal oxide that can be used for oxide 530a or oxide 530b. Things can be used.

[0173] The energy of the conduction band minimum of the oxide 530a and the oxide 530c is It is preferable that the energy of the oxide is higher than the energy of the bottom of the conduction band of oxide b. The electron affinity of 530a and oxide 530c is smaller than the electron affinity of oxide 530b. It is preferable.

[0174] Here, at the junctions of oxide 530a, oxide 530b, and oxide 530c, The energy level of the lower conduction band edge changes gradually. The energy level of the conduction band minimum at the junction of 530b and oxide 530c is continuous. In order to achieve this, the oxide 5 At the interface between oxide 530a and oxide 530b, and at the interface between oxide 530b and oxide 530c This is advantageous in that the defect level density of the mixed layer formed by this method is reduced.

[0175] Specifically, oxide 530a and oxide 530b, and oxide 530b and oxide 530c are oxides. By having a common element other than the element (as the main component), a mixed layer with low defect level density is formed. For example, if the oxide 530b is an In-Ga-Zn oxide, the oxide 530b may be an In-Ga-Zn oxide. 30a and oxide 530c, In-Ga-Zn oxide, Ga-Zn oxide, oxide Gallium or the like may be used.

[0176] At this time, the main path of the carriers is the oxide 530b. By configuring the oxide 530c as described above, the interface between the oxide 530a and the oxide 530b and the oxide The defect state density at the interface between the substrate 530b and the oxide 530c can be reduced. Therefore, the influence of interface scattering on carrier conduction is reduced, and the transistor 500 has a high On-current can be obtained.

[0177] On the oxide 530b, a conductor 542a is formed, which functions as a source electrode and a drain electrode. The conductor 542a and the conductor 542b are provided as follows: , aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum , tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconia Sodium, beryllium, indium, ruthenium, iridium, strontium, lanthanum or an alloy containing the above metal elements, or It is preferable to use a combination of alloys, for example, tantalum nitride, titanium nitride, tantalum titanium and aluminum nitrides, tantalum and aluminum nitrides, Ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, lanthanum It is preferable to use oxides containing nickel. , nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide Ruthenium, ruthenium nitride, oxides containing strontium and ruthenium, lanthanum and nickel Oxides containing oxygen are conductive materials that are resistant to oxidation or that maintain conductivity even after absorbing oxygen. Furthermore, metal nitride films such as tantalum nitride are preferable because they can be easily etched by hydrogen or oxygen. It is preferable because it has a barrier property against elements.

[0178] In addition, although the conductor 542a and the conductor 542b are shown as single-layer structures in FIG. A laminated structure of two or more layers may be used. For example, a tantalum nitride film and a tungsten film may be laminated. Alternatively, a titanium film and an aluminum film may be stacked. Two-layer structure with aluminum film laminated, copper film on copper-magnesium-aluminum alloy film Two-layer structure with copper film laminated on titanium film, two-layer structure with copper film laminated on tungsten film A two-layer structure may also be used.

[0179] Also, a titanium film or titanium nitride film and an aluminum film overlaid on the titanium film or titanium nitride film are used. A titanium film or a copper film is laminated, and a titanium film or a titanium nitride film is further formed on the aluminum film or a copper film. Three-layer structure: a molybdenum film or molybdenum nitride film and a molybdenum film or molybdenum nitride film. An aluminum film or copper film is laminated on top of the molybdenum film, and then a molybdenum film or There are three-layer structures in which a molybdenum nitride film is formed. A transparent conductive material containing zinc oxide may also be used.

[0180] As shown in FIG. 10A, the oxide 530 and the conductor 542a (conductor 542b) At the interface and its vicinity, a region 543a and a region 543b are formed as low resistance regions. In this case, the region 543a functions as either a source region or a drain region. The region 543b functions as the other of the source region and the drain region. A channel forming region is formed in the region sandwiched between region 543a and region 543b.

[0181] By providing the conductor 542a (conductor 542b) so as to be in contact with the oxide 530, The oxygen concentration in the region 543a (region 543b) may decrease. The metal contained in the conductor 542a (conductor 542b) and the oxide 530 are mixed in the region 543b. In such a case, a metal compound layer containing the metal compound may be formed in the region 543a (region The carrier density in the region 543a (region 543b) increases, and the region 543a (region 543b) becomes a low resistance region. do.

[0182] The insulator 544 is provided to cover the conductor 542a and the conductor 542b. The insulator 544 prevents oxidation of the oxide 542a and the conductor 542b. 530 and may be provided to be in contact with the insulator 524.

[0183] Insulator 544 includes hafnium, aluminum, gallium, yttrium, and zirconium. Aluminum, tungsten, titanium, tantalum, nickel, germanium, neodymium, lanthanum, or a metal oxide containing one or more selected from magnesium, etc. The insulator 544 may be made of silicon nitride oxide, silicon nitride, or the like. can also be used.

[0184] In particular, the insulator 544 may be an oxide of aluminum or hafnium, or both. Insulators containing aluminum oxide, hafnium oxide, aluminum, and hafnium It is preferable to use oxides containing hafnium (hafnium aluminate). Hafnium aluminate has higher heat resistance than hafnium oxide. This is preferable because it is difficult to crystallize during the heat treatment. 542b is a material that is oxidation-resistant, or the conductivity does not decrease significantly even when it absorbs oxygen. In this case, the insulator 544 is not an essential component. Just do that.

[0185] By providing the insulator 544, impurities such as water and hydrogen contained in the insulator 580 are converted into acids. The oxide 530c is prevented from diffusing into the oxide 530b through the insulator 550. In addition, the excess oxygen contained in the insulator 580 can prevent the conductor 560 from being oxidized. It is possible.

[0186] The insulator 550 functions as a first gate insulating film. It is preferable that the insulator 550 is disposed in contact with the inside (top and side surfaces) of the Similar to the insulator 524, an insulator containing excess oxygen and releasing oxygen when heated is used. It is preferable to form it using a

[0187] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxide, and nitride silicon dioxide, fluorine-doped silicon dioxide, carbon-doped silicon dioxide, carbon, and Silicon oxide doped with nitrogen and silicon oxide having vacancies can be used. Silicon oxide and silicon oxynitride are preferred because they are stable to heat.

[0188] An insulator that releases oxygen when heated is used as an insulator 550 and is attached to the top surface of the oxide 530c. By providing the oxide 530b as the insulating layer 550, the oxide 530c passes through the insulating layer 550. Oxygen can be effectively supplied to the channel formation region. Preferably, the concentration of impurities such as water or hydrogen in the insulator 550 is reduced. The thickness of the insulator 550 is preferably 1 nm or more and 20 nm or less.

[0189] In addition, in order to efficiently supply excess oxygen contained in the insulator 550 to the oxide 530, A metal oxide may be provided between the body 550 and the conductor 560. The metal oxide may be an insulator. It is preferable to suppress the diffusion of oxygen from 550 to the conductor 560. The metal oxide prevents excess oxygen from diffusing from the insulator 550 to the conductor 560. In other words, it is possible to suppress a decrease in the amount of excess oxygen supplied to the oxide 530. This can prevent the conductor 560 from being oxidized by excess oxygen. Any material that can be used for the insulator 544 may be used.

[0190] Note that the insulator 550 may have a stacked structure similar to the second gate insulating film. As the miniaturization and high integration of devices progresses, the gate insulating film becomes thinner, which reduces leakage current and other problems. Therefore, the insulator that functions as the gate insulating film is made of high-k material. By using a laminated structure of a thermally stable material and a thin film of a thin film, It is possible to reduce the gate potential during transistor operation. It may have a laminated structure.

[0191] The conductor 560 functioning as the first gate electrode has a two-layer structure in FIGS. 10A and 10B. However, it may have a single layer structure or a laminated structure of three or more layers.

[0192] The conductor 560a is a hydrogen atom, a hydrogen molecule, a water molecule, a nitrogen atom, a nitrogen molecule, a nitrogen oxide molecule ( Conductive material with the function of suppressing the diffusion of impurities such as N2O, NO, NO2, etc., copper atoms, etc. It is preferable to use a material containing at least oxygen (for example, oxygen atoms, oxygen molecules, etc.). It is preferable to use a conductive material that has the function of suppressing the diffusion of the conductor 56. Oa has the function of suppressing oxygen diffusion, so the oxygen contained in the insulator 550 This can prevent the conductor 560b from being oxidized and the conductivity from decreasing. Examples of conductive materials that have the function of suppressing this include tantalum, tantalum nitride, and ruthenium. It is preferable to use ruthenium or ruthenium oxide as the conductor 560a. In this case, an oxide semiconductor that can be used for the oxide 530 can be used. By forming a film of conductor 560b by sputtering, the electrical resistance value of conductor 560a is reduced. This is called an OC (Oxide Conductor) electrode. This can be done.

[0193] The conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. In addition, since the conductor 560b also functions as a wiring, It is preferable to use a highly conductive material, such as tungsten, copper, or aluminum. The conductor 560b may be a conductive material containing silicon as a main component. For example, a laminated structure of titanium or titanium nitride and the above conductive material may be used. good.

[0194] The insulator 580 is provided on the conductor 542a and the conductor 542b via the insulator 544. Preferably, the insulator 580 has an excess oxygen region. For example, the insulator 58 0, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, fluorine silicon oxide doped with carbon, silicon oxide doped with carbon, and acid doped with nitrogen. It is particularly preferable that the insulating layer 100 has a silicon oxide, a silicon oxide having pores, or a resin. Silicon oxide and silicon oxynitride are preferred because they are thermally stable. Silicon oxide and silicon oxide with vacancies easily form excess oxygen regions in later processes. This is preferable because it is possible to

[0195] The insulator 580 preferably has an excess oxygen region. By providing the insulator 580 in contact with the oxide 530c, the oxygen in the insulator 580 is converted into the oxide 530c, the oxide 530 can be efficiently supplied. It is preferable that the concentration of impurities such as water or hydrogen in the oxygen-containing gas is reduced.

[0196] The opening in the insulator 580 is formed to overlap the region between the conductor 542a and the conductor 542b. As a result, the conductor 560 is inserted through the opening in the insulator 580 and the conductor 542a and the conductor 542b. It is formed so as to be embedded in the region sandwiched between 542b.

[0197] In miniaturizing semiconductor devices, it is required to shorten the gate length. Therefore, the thickness of the conductor 560 must be increased. As a result, the conductor 560 can have a shape with a high aspect ratio. In order to embed the conductor 560 in the opening of the insulator 580, the conductor 560 is formed to have an aspect ratio Even if the shape is high, the conductor 560 can be formed without collapsing during the process. do.

[0198] The insulator 574 is connected to the top surface of the insulator 580, the top surface of the conductor 560, and the top surface of the insulator 550. The insulator 574 is preferably provided in contact with the , insulator 550, and insulator 580. From this excess oxygen region, oxygen can be supplied into the oxide 530 .

[0199] For example, the insulator 574 may be hafnium, aluminum, gallium, yttrium, or di zinc, tungsten, titanium, tantalum, nickel, germanium, or magnesium Metal oxides containing one or more metals selected from the group consisting of sodium, do.

[0200] In particular, aluminum oxide has a high barrier property and is a thin film of 0.5 nm to 3.0 nm. Therefore, the diffusion of hydrogen and nitrogen can be suppressed even if the sputtering method is used. The aluminum oxide film formed by this method is both an oxygen source and a barrier to impurities such as hydrogen. It can also function as a membrane.

[0201] In addition, it is preferable to provide an insulator 581 that functions as an interlayer film over the insulator 574. The insulator 581, like the insulator 524, has a low impurity concentration such as water or hydrogen. It is preferably reduced.

[0202] Also, openings formed in the insulators 581, 574, 580, and 544 Conductor 540a and conductor 540b are placed in the mouth. The conductors 540a and 540b are provided opposite each other with the conductor 560 in between. b has the same configuration as conductor 546 and conductor 548 described later.

[0203] An insulator 582 is provided on the insulator 581. The insulator 582 is resistant to oxygen and hydrogen. Therefore, the insulator 582 is preferably made of an insulating material having a barrier property. The insulator 582 may be made of a material similar to that of the insulator 514. For example, the insulator 582 may be made of aluminum oxide. It is preferable to use metal oxides such as tantalum oxide, hafnium oxide, and the like.

[0204] In particular, aluminum oxide is a material that can absorb oxygen and hydrogen, which can cause fluctuations in the electrical characteristics of transistors. Therefore, it has a high blocking effect that prevents impurities such as acid and moisture from passing through the membrane. Aluminum oxide is resistant to hydrogen, moisture, etc. during and after the transistor manufacturing process. It is possible to prevent impurities from being mixed into the transistor 500. This can suppress the release of oxygen from the oxide that makes up the transistor. Suitable for use as a protective film against 500.

[0205] In addition, an insulator 586 is provided on the insulator 582. The insulator 586 is 20 can be used. In addition, these insulators have a relatively low dielectric constant. By applying the material, it is possible to reduce the parasitic capacitance that occurs between wiring. For example, The body 586 can be a silicon oxide film, a silicon oxynitride film, or the like.

[0206] Also, the insulator 520, the insulator 522, the insulator 524, the insulator 544, the insulator 580, the insulator The body 574, the insulator 581, the insulator 582, and the insulator 586 are provided with the conductor 546 and and a conductor 548 and the like are embedded therein.

[0207] The conductor 546 and the conductor 548 are connected to the capacitor 600, the transistor 500, or the transistor The conductor 546 functions as a plug or wiring that connects to the resistor 300. The conductor 548 may be formed using the same material as the conductor 328 and the conductor 330. can be done.

[0208] After the transistor 500 is formed, an opening is formed to surround the transistor 500. An insulator having high barrier properties against hydrogen or water may be formed so as to cover the opening. By encasing the transistor 500 in the insulator with high barrier properties, moisture and It is possible to prevent the intrusion of hydrogen and oxygen. Alternatively, the transistor may be wrapped in an insulator that has a high barrier property against hydrogen or water. When forming an opening to surround the transistor 500, for example, the insulator 522 or the insulator 5 14, and the burr 522 or 514 is in contact with the insulator 522 or 514. If a highly insulating material is formed, it can be used as part of the manufacturing process of the transistor 500. In addition, examples of insulators with high barrier properties against hydrogen or water include: A material similar to that of the insulator 522 or the insulator 514 may be used.

[0209] Next, a capacitor 600 is provided above the transistor 500. The capacitor 600 has the following characteristics: It has a conductor 610, a conductor 620, and an insulator 630.

[0210] Moreover, a conductor 612 may be provided on the conductor 546 and the conductor 548. 12 has a function as a plug or wiring that connects to the transistor 500. The conductive body 610 functions as an electrode of the capacitor 600. The body 610 can be formed simultaneously.

[0211] The conductor 612 and the conductor 610 may be made of molybdenum, titanium, tantalum, or tungsten. a metal film containing an element selected from aluminum, copper, chromium, neodymium, and scandium; Or a metal nitride film containing the above-mentioned elements (tantalum nitride film, titanium nitride film, molybdenum nitride film, etc.) Indium tin oxide (ITO) or tungsten nitride (Tungsten nitride) can be used. Indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide oxide, indium oxide with titanium oxide, indium tin oxide with titanium oxide, Conductive materials such as indium zinc oxide and indium tin oxide with added silicon oxide are used You can also do this.

[0212] In this embodiment, the conductor 612 and the conductor 610 are shown as a single layer structure. For example, a conductive material having a barrier property and a conductive material having a barrier property may be laminated. Conductors with barrier properties are placed between the highly conductive conductors and those with high conductivity. A highly adhesive conductor may be formed.

[0213] The conductor 620 is provided so as to overlap with the conductor 610 with the insulator 630 interposed therebetween. The conductor 620 is made of a conductive material such as a metal material, an alloy material, or a metal oxide material. High-melting-point materials such as tungsten and molybdenum, which have both heat resistance and electrical conductivity, are used. It is preferable to use tungsten, and it is particularly preferable to use tungsten. When forming the structure at the same time as other structures, low-resistance metal materials such as Cu (copper) and Al (aluminum) are used. It is best to use a

[0214] An insulator 640 is provided on the conductor 620 and the insulator 630. The insulator 640 can be formed using a material similar to that of the insulator 320. It may also function as a planarizing film that covers the underlying unevenness.

[0215] By using this structure, a semiconductor device using a transistor having an oxide semiconductor This allows for miniaturization or high integration.

[0216] Examples of a substrate that can be used for a semiconductor device of one embodiment of the present invention include a glass substrate and a quartz substrate. , sapphire substrate, ceramic substrate, metal substrate (e.g., stainless steel substrate, Substrate with steel foil, tungsten substrate, tungsten foil semiconductor substrates (e.g., single crystal semiconductor substrates, polycrystalline semiconductor substrates, or compound semiconductor substrates), SOI (Silicon on Insulator) substrate In addition, a material having heat resistance capable of withstanding the processing temperature of this embodiment can be used. A plastic substrate may also be used. An example of a glass substrate is barium borosilicate glass. Glass, aluminosilicate glass, or aluminoborosilicate glass, or soda lime Glass, etc. Alternatively, crystallized glass, etc. can be used.

[0217] Alternatively, the substrate may be a flexible substrate, a laminated film, a paper containing a fibrous material, or A flexible substrate, a laminated film, a base film, etc. can be used. Examples of such materials include polyethylene terephthalate. (PET), polyethylene naphthalate (PEN), polyethersulfone (PES) , and plastics such as polytetrafluoroethylene (PTFE). An example is a synthetic resin such as acrylic. Another example is polypropylene. Examples include polyethylene, polyester, polyvinyl fluoride, or polyvinyl chloride. Examples include polyamide, polyimide, aramid, epoxy, inorganic vapor deposition film, and paper. In particular, transistors are manufactured using semiconductor substrates, single crystal substrates, or SOI substrates. By manufacturing the capacitors, there is little variation in characteristics, size, or shape, and the current It is possible to manufacture transistors with high performance and small size. By configuring a circuit using a MOS transistor, it is possible to reduce the power consumption of the circuit or to increase the integration density of the circuit. can be done.

[0218] In addition, a flexible substrate is used as the substrate, and transistors, resistors, and Alternatively, a substrate and a transistor, a resistor, and / or a capacitor may be formed. Alternatively, a release layer may be provided between the capacitors and the like. Or, after the whole process is completed, it can be separated from the substrate and used for transferring to another substrate. In this case, transistors, resistors, and / or capacitors are mounted on substrates with poor heat resistance or flexible substrates. The above-mentioned peeling layer may be formed of, for example, a tungsten film and a silicon oxide film. A laminated structure of an inorganic film and a substrate, or a structure in which an organic resin film such as polyimide is formed on a substrate Alternatively, a silicon film containing hydrogen or the like can be used.

[0219] In other words, even if a semiconductor device is formed on a certain substrate and then transferred to another substrate, An example of a substrate onto which a semiconductor device is transferred is a substrate on which the above-described transistor is formed. In addition to the substrates that can be used, paper substrates, cellophane substrates, aramid film substrates, polyimide film substrates, Film substrate, stone substrate, wood substrate, fabric substrate (natural fibers (silk, cotton, linen), synthetic fibers (nylon) Polyurethane, polyester) or regenerated fiber (acetate, cupra, rayon , recycled polyester), leather substrates, or rubber substrates. By using the plate, it is possible to manufacture flexible semiconductor devices and to manufacture semiconductor devices that are not easily broken. It is possible to provide heat resistance, reduce weight, or reduce thickness.

[0220] (Embodiment 5) In this embodiment, an example of an electronic device using a thin-film secondary battery will be described with reference to FIGS. 11 and 12. Explanations will be given.

[0221] FIG. 11B shows an IC card, which is an example of an application device using the thin-film secondary battery according to the present invention. The power obtained by receiving the radio wave 3005 is transferred to the thin-film secondary battery 3003 shown in FIG. 001. The IC card 3000 contains an antenna and IC3004 The IC card 3000 is equipped with a thin-film secondary battery 3001. D3002 and photo 3003 are attached. The thin-film secondary battery 3001 is charged. It is also possible to use power to transmit signals such as authentication signals from the antenna.

[0222] Also, an active matrix display device may be provided in place of the photo 3003. Matrix display devices include reflective LCDs, organic EL displays, and electronic paper. There are cases where an active matrix display device displays an image (moving or still image) or time. The power for the active matrix display device is supplied from a thin-film secondary battery 3001. can be provided.

[0223] Since IC cards use plastic substrates, organic EL displays using flexible substrates are A display device is preferred.

[0224] A solar cell may also be provided. When irradiated with external light, it absorbs the light, generates electricity, and uses the electricity. The power can be charged into the thin-film secondary battery 3001.

[0225] Furthermore, thin-film secondary batteries are not limited to IC cards, but can also be used to power wireless sensors used in automobiles. It can be used as a power source, a secondary battery for MEMS devices, etc.

[0226] FIG. 12A shows an example of a wearable device. The wearable device has a power source and In addition, the user must ensure that the device is water-resistant when used in daily life or outdoors. To improve the charging experience, we have implemented wireless charging in addition to wired charging, which has an exposed connector. There is a demand for wearable devices that can also be charged.

[0227] For example, a secondary battery can be mounted on a glasses-type device 400 as shown in FIG. 12A. The eyeglass-type device 400 has a frame 400a and a display unit 400b. By mounting a secondary battery in the temple portion of the frame 400a, the device is lightweight and The eyeglass-type device 400 can be well-balanced and can be used continuously for a long time. The thin-film secondary battery shown in embodiment 1 may be provided, and space saving can be achieved by making the housing smaller. It is possible to realize a configuration in which this is possible.

[0228] In addition, a secondary battery can be installed in the headset type device 401. Headset The microphone device 401 includes at least a microphone unit 401a, a flexible pipe 401b, and The flexible pipe 401b has an earphone section 401c. The thin-film secondary battery shown in the first embodiment may be provided. It is possible to realize a configuration that can accommodate space saving due to the miniaturization of the housing.

[0229] Furthermore, a secondary battery can be installed in the device 402 that can be attached directly to the body. A secondary battery 402b can be provided inside the thin housing 402a of the device 402. The thin-film secondary battery shown in the first embodiment may be provided, and the space saving due to the miniaturization of the housing may be achieved. It is possible to realize a configuration that can accommodate this.

[0230] In addition, a secondary battery can be installed in the device 403 that can be attached to clothing. A secondary battery 403b can be provided inside the thin housing 403a of the sensor 403. The thin-film secondary battery shown in form 1 may be included, and space saving is achieved by miniaturizing the housing. It is possible to realize a configuration in which this is possible.

[0231] In addition, a secondary battery can be mounted on the belt type device 406. 06 has a belt part 406a and a wireless power receiving part 406b, and the belt part 406 A secondary battery can be mounted inside a. This allows for a configuration that can accommodate space savings associated with a smaller housing. do.

[0232] In addition, a secondary battery can be mounted on the wristwatch type device 405. 05 has a display part 405a and a belt part 405b, and A secondary battery can be provided in the thin film secondary battery shown in the third embodiment. This allows for a configuration that can accommodate space-saving requirements that accompany a smaller housing.

[0233] The display unit 405a can display not only the time but also various information such as incoming emails and phone calls. This can be done.

[0234] The wristwatch type device 405 is a wearable device that is worn directly on the wrist. Therefore, sensors for measuring the user's pulse, blood pressure, etc. may be installed. It can accumulate data on your health and lifestyle, and can be used to help you maintain your health.

[0235] A detailed description of the wristwatch type device 405 shown in FIG. 12A will be given below.

[0236] FIG. 12B shows a perspective view of the wristwatch type device 405 removed from the wrist.

[0237] A side view is shown in Fig. 12C. Fig. 12C shows the state in which a secondary battery 913 is built in. The secondary battery 913 is the thin-film secondary battery described in the third embodiment. 913 is provided at a position overlapping the display unit 405a, and is small and lightweight. [Explanation of symbols]

[0238] 101: Substrate, 201: Positive electrode, 202: Solid electrolyte layer, 203: Negative electrode, 204: Positive electrode active material 205: negative electrode active material layer; 206: protective layer; 400: eyeglass-type device; 400a: foil frame, 400b: display unit, 401: headset type device, 401a: microphone unit, 4 01b: flexible pipe, 401c: earphone part, 402: device, 402a: Housing, 402b: secondary battery, 403: device, 403a: housing, 403b: secondary battery, 405: Wristwatch type device, 405a: Display unit, 405b: Belt unit, 406: Belt type Device, 406a: belt part, 406b: wireless power supply receiving part, 3000: IC card 3001: Thin film secondary battery, 3002: ID, 3003: Photo, 3004: IC, 3 005: Radio Waves

Claims

1. a positive electrode active material layer; a negative electrode active material layer disposed opposite the positive electrode active material layer; a solid electrolyte layer between the positive electrode active material layer and the negative electrode active material layer, the solid electrolyte layer containing silicon, oxygen, lithium, and carbon; a ratio of oxygen to silicon (O / Si) in the solid electrolyte layer is greater than 1 and less than 2.

2. a positive electrode active material layer; a negative electrode active material layer disposed opposite the positive electrode active material layer; a solid electrolyte layer between the positive electrode active material layer and the negative electrode active material layer, the solid electrolyte layer containing silicon, oxygen, lithium, and carbon; a ratio of oxygen to silicon (O / Si) of the solid electrolyte layer determined from EDX measurement results of a cross section of the solid electrolyte layer is greater than 1 and less than 2.

3. 3. The solid secondary battery according to claim 1, wherein the solid electrolyte layer further contains nitrogen.

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