WO2011086940A1 - In-Ga-O系酸化物焼結体、ターゲット、酸化物半導体薄膜及びこれらの製造方法 - Google Patents
In-Ga-O系酸化物焼結体、ターゲット、酸化物半導体薄膜及びこれらの製造方法 Download PDFInfo
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- WO2011086940A1 WO2011086940A1 PCT/JP2011/000169 JP2011000169W WO2011086940A1 WO 2011086940 A1 WO2011086940 A1 WO 2011086940A1 JP 2011000169 W JP2011000169 W JP 2011000169W WO 2011086940 A1 WO2011086940 A1 WO 2011086940A1
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Definitions
- the present invention relates to an In—Ga—O-based oxide sintered body, a target, an oxide semiconductor thin film, a manufacturing method thereof, and a thin film transistor including the oxide semiconductor thin film.
- TFTs thin film transistors
- LCD liquid crystal display devices
- EL electroluminescence display devices
- FED field emission displays
- a silicon semiconductor compound As a material for a semiconductor layer (channel layer) which is a main member of a field effect transistor, a silicon semiconductor compound is most widely used.
- a silicon single crystal is used for a high-frequency amplifying element or an integrated circuit element that requires high-speed operation.
- an amorphous silicon semiconductor (amorphous silicon) is used for a liquid crystal driving element or the like because of a demand for a large area.
- an amorphous silicon thin film can be formed at a relatively low temperature, its switching speed is slower than that of a crystalline thin film, so when used as a switching element for driving a display device, it may not be able to follow the display of high-speed movies. is there.
- amorphous silicon having a mobility of 0.5 to 1 cm 2 / Vs could be used, but when the resolution is SXGA, UXGA, QXGA or higher, 2 cm 2 / Mobility greater than Vs is required.
- the driving frequency is increased in order to improve the image quality, higher mobility is required.
- the crystalline silicon-based thin film has a high mobility
- problems such as requiring a large amount of energy and the number of processes for manufacturing, and a problem that it is difficult to increase the area.
- laser annealing using a high temperature of 800 ° C. or higher and expensive equipment is necessary.
- a crystalline silicon-based thin film is difficult to reduce costs such as a reduction in the number of masks because the element configuration of a TFT is usually limited to a top gate configuration.
- an oxide semiconductor thin film is manufactured by sputtering using a target (sputtering target) made of an oxide sintered body.
- Patent Documents 1, 2 and 3 the general formula In 2 Ga 2 ZnO 7, the target made of a compound showing a homologous crystal structure represented by InGaZnO 4 has been disclosed (Patent Documents 1, 2 and 3).
- a reduction treatment at a high temperature after sintering is required to reduce the resistance of the target. It was.
- the characteristics and deposition rate of the obtained film change greatly, abnormal discharge occurs due to abnormal growth of InGaZnO 4 and In 2 Ga 2 ZnO 7 , and generation of particles during film formation occurs. There were many problems. If abnormal discharge frequently occurs, the plasma discharge state becomes unstable, and stable film formation is not performed, which adversely affects the film characteristics.
- Patent Document 4 A sputtering target in which indium oxide is co-doped with gallium oxide and germanium oxide has been developed for use as a conductive film.
- Nodule can be suppressed by replacing and solid-dissolving gallium atoms and germanium atoms in the indium oxide component in the sintered body so that the maximum grain size of the crystal is 5 ⁇ m or less.
- the comparative example of Patent Document 4 shows the production of an In 2 O 3 target doped with only Ga and the presence or absence of nodule generation, and it is reported that the generation of nodule is remarkable.
- An object of the present invention is to provide an oxide sintered body that suppresses abnormal discharge that occurs when an oxide semiconductor thin film is formed using a sputtering method, and that allows the oxide semiconductor thin film to be obtained stably and reproducibly. It is to be.
- the present inventors use a sputtering target having an atomic ratio of Ga / (In + Ga) of 0.10 to 0.15 in an oxide sintered body made of gallium element, indium element, and oxygen element, to form a direct current sputtering method. Then, an oxide semiconductor thin film was formed.
- a sputtering target having an atomic ratio of Ga / (In + Ga) of 0.10 to 0.15 in an oxide sintered body made of gallium element, indium element, and oxygen element, to form a direct current sputtering method. Then, an oxide semiconductor thin film was formed.
- the target indium oxide crystal substantially has a bixbite structure
- abnormal discharge does not occur even when DC power is applied, but the crystal is added to the bixbite structure in addition to GaInO 3 or the like. It has been found that abnormal discharge frequently occurs when the structure including the other structure is included.
- the present invention has been completed by finding that abnormal discharge is suppressed in a target substantially consisting of a bixbit
- the crystal structure consists essentially of indium oxide exhibiting a bixbite structure; Gallium atoms are dissolved in the indium oxide, An oxide sintered body having an atomic ratio Ga / (Ga + In) of 0.10 to 0.15. 2.
- An indium oxide powder having an average particle size of 1.2 ⁇ m or less and a gallium oxide powder having an average particle size of 1.2 ⁇ m or less are mixed so that the atomic ratio Ga / (Ga + In) is 0.10 to 0.15. Preparing a mixed powder; 3.
- the method for producing an oxide sintered body according to 1 or 2 comprising a step of producing a compact by molding the mixed powder and a step of firing the compact at 1450 ° C. to 1650 ° C. for 10 hours or more. 4). 4. The method for producing an oxide sintered body according to 3, wherein the firing is performed in an oxidizing gas atmosphere.
- a display device comprising the thin film transistor according to 9.8.
- the oxide sintered compact which can suppress the abnormal discharge which generate
- FIG. 3 is a diagram showing the results of X-ray diffraction measurement of a sintered body produced in Example 1.
- FIG. 6 is a diagram showing a result of X-ray diffraction measurement of a sintered body produced in Example 2.
- FIG. 6 is a diagram showing the results of X-ray diffraction measurement of a sintered body produced in Example 3. It is a figure which shows the X-ray-diffraction measurement result of the sintered compact manufactured in Example 4.
- FIG. 6 is a diagram showing a result of X-ray diffraction measurement of a sintered body produced in Example 5.
- FIG. 6 is a diagram showing the results of X-ray diffraction measurement of a sintered body produced in Example 6.
- FIG. 4 is a diagram showing a result of X-ray diffraction measurement of a sintered body produced in Comparative Example 1.
- 6 is a diagram showing the X-ray diffraction measurement results of a sintered body produced in Comparative Example 2.
- FIG. It is a figure which shows the X-ray-diffraction measurement result of the sintered compact manufactured by the comparative example 3.
- the oxide sintered body of the present invention is made of indium oxide whose crystal structure substantially has a bixbyite structure, gallium atoms are solid-solved in the indium oxide, and the atomic ratio Ga / (Ga + In) is 0.10 to 0.15.
- the oxide sintered body of the present invention is composed of a single phase of indium oxide having a Bigsbyte structure in which gallium atoms are dissolved, when sputtering a target composed of the oxide sintered body of the present invention, abnormal discharge is caused. Can be suppressed.
- the oxide sintered body of the present invention is composed of a single phase of indium oxide having a Bigsbite structure in which gallium atoms are dissolved, the generation of cracks and nodules in the target composed of the oxide sintered body of the present invention is prevented. Can be reduced. Therefore, the oxide sintered body of the present invention can form a high-quality oxide semiconductor thin film efficiently, inexpensively and with energy saving.
- the Bixbite structure can be confirmed by X-ray diffraction.
- substantially means that the effect of the present invention is attributable to the above bixbite structure, or 90% by volume or more, preferably 95% by volume or more, and more preferably 98% by volume or more of the crystal structure. It means indium oxide showing a bite structure.
- the oxide sintered body of the present invention has a crystal structure of 90% by volume or more, preferably 95% by volume or more, and more preferably 98% by volume or more.
- 90% by volume or more is composed of a crystal structure, and 90% by volume or more of the crystal structure is indium oxide having a bixbite structure. Volume fraction can be calculated from peak analysis of X-ray diffraction.
- Ga can be uniformly dispersed in the indium oxide crystal.
- the atomic ratio Ga / (Ga + In) is more than 0.15, Ga does not dissolve in the bixbite structure of indium oxide, and another crystal structure such as GaInO 3 may be precipitated.
- the oxide sintered body of the present invention includes another crystal structure such as GaInO 3 , abnormal sputtering is likely to occur and electrons are scattered when a target made of the oxide sintered body of the present invention is sputtered. As a result, the mobility may be reduced or crystallization of indium oxide may be hindered.
- the impedance of the discharge system including the target fluctuates during sputtering because the target is non-uniform and there is a portion where the specific resistance is locally different.
- the portion where the specific resistance is locally different is a crystal such as GaInO 3 , and reducing the size and number density of these crystals is effective in suppressing abnormal discharge.
- the atomic ratio Ga / (Ga + In) is less than 0.10, when a thin film is formed using the target made of the oxide sintered body of the present invention, there is a possibility that microcrystals are generated in the thin film.
- the thin film is heated in a post-treatment step, secondary crystallization may occur, leading to an increase in carrier concentration as mobility decreases and oxygen defects increase.
- the atomic ratio Ga / (Ga + In) of gallium metal and indium metal is preferably 0.10 to 0.15, more preferably 0.11 to 0.15, and further preferably 0.12 to 0.15. 0.15, particularly preferably Ga / (Ga + In) is 0.12 to 0.14.
- the atomic ratio of each element contained in the oxide sintered body of the present invention can be determined by analyzing the contained elements using an inductively coupled plasma emission spectrometer (ICP-AES).
- ICP-AES inductively coupled plasma emission spectrometer
- a solution sample is atomized with a nebulizer and introduced into an argon plasma (about 6000 to 8000 ° C.)
- the elements in the sample are excited by absorbing thermal energy, and orbital electrons are generated. Move from the ground state to a high energy level orbit. These orbital electrons move to a lower energy level orbit in about 10 ⁇ 7 to 10 ⁇ 8 seconds. At this time, the energy difference is emitted as light to emit light.
- the presence of the element can be confirmed by the presence or absence of the spectral line (qualitative analysis).
- the magnitude (luminescence intensity) of each spectral line is proportional to the number of elements in the sample, the sample concentration can be obtained by comparing with a standard solution having a known concentration (quantitative analysis).
- the atomic ratio of each element can be calculated
- the density of the oxide sintered body of the present invention is preferably 6.2 g / cm 3 or more, more preferably 6.4 g / cm 3 or more.
- the density is less than 6.2 g / cm 3
- the surface of the sputtering target made of the oxide sintered body of the present invention may be blackened, abnormal discharge may be induced, and the sputtering rate may be reduced.
- the density is particularly preferably 6.2 g / cm 3 or more and 7.1 g / cm 3 or less.
- the maximum particle size of the indium oxide crystal in which gallium atoms in the oxide sintered body are dissolved is desirably 5 ⁇ m or less.
- the grain size of the indium oxide crystal exceeds 5 ⁇ m, it may cause nodules.
- the cutting speed varies depending on the direction of the crystal plane, and irregularities are generated on the target surface.
- the size of the unevenness depends on the crystal grain size present in the sintered body, and in the target made of a sintered body having a large crystal grain size, the unevenness becomes large and nodules are generated from the convex part. It is done.
- the maximum particle size of the indium oxide crystal is such that when the shape of the sputtering target made of the oxide sintered body of the present invention is a circle, the center point (one place) of the circle and two centers orthogonal to each other at the center point At a total of five intermediate points (four locations) between the center point on the line and the peripheral edge, or when the sputtering target has a quadrilateral shape, the center point (one location) and the center point on the diagonal of the quadrangle Measure the maximum diameter of the largest particles observed in a 100 ⁇ m square frame at a total of five points at the midpoint (4 points) with the corner, and determine the maximum particle size in each of these five frames. Average value of particle diameter. As for the particle diameter, the major axis of the crystal grain is measured. The crystal grains can be observed with a scanning electron microscope (SEM).
- gallium atoms are dissolved and dispersed in indium oxide, but the aggregate of dispersed gallium atoms is preferably less than 1 ⁇ m.
- Stable sputter discharge can be achieved by finely dispersing gallium atoms.
- the diameter of the aggregate of gallium atoms can be measured by EPMA (electron beam microanalyzer).
- the film formation rate during DC sputtering depends on the specific resistance of the oxide sintered body of the sputtering target. Therefore, from the viewpoint of productivity, the specific resistance of the oxide sintered body is preferably as low as possible, and the specific resistance of the oxide sintered body of the present invention is preferably 10 ⁇ cm or less, more preferably 1 ⁇ cm or less. . On the other hand, when the specific resistance of the oxide sintered body is more than 10 ⁇ cm, it may be difficult to perform stable film formation by direct current sputtering. In addition, the specific resistance of the oxide sintered body can be reduced by a reduction process in which heating is performed in a non-oxidizing atmosphere such as nitrogen in the process of manufacturing the sintered body described later.
- the specific resistance of the oxide sintered body is 10 ⁇ cm or less, stable DC sputtering cannot always be performed. Even if the specific resistance of the entire oxide sintered body is 10 ⁇ cm or less, the oxide sintered body locally contains a high-resistance material phase exceeding 10 ⁇ cm (for example, the above GaInO 3 phase). Since this portion is charged by irradiation with sputtering gas ions, abnormal discharge occurs, and DC sputtering cannot be performed stably. Therefore, it is important that the specific resistance of the entire oxide sintered body is 10 ⁇ cm or less without locally including the high resistance phase.
- the oxide sintered body of the present invention is composed of gallium element, indium element, and oxygen element, and is substantially composed of indium oxide having a bigsbite structure, but contains other inevitable impurities as long as the effect of the present invention is not impaired. You may go out.
- an indium oxide powder having an average particle size of 1.2 ⁇ m or less and a gallium oxide powder having an average particle size of 1.2 ⁇ m or less have an atomic ratio Ga / (Ga + In) of 0.
- the oxide sintered body of the present invention is not limited by its production method, and can be produced from a combination of gallium metal and indium oxide. However, it is preferable to use indium oxide and gallium oxide as a raw material powder. In addition, when using indium oxide and gallium metal as the raw material powder, gallium metal particles are present in the obtained oxide sintered body, and the metal particles on the target surface are melted during the film formation. There is a possibility that the composition of the obtained film and the composition of the oxide sintered body are greatly different from each other without being released.
- Both the indium oxide powder and the gallium oxide powder which are raw material powders, have an average particle size of 1.2 ⁇ m or less, preferably 1.0 ⁇ m or less.
- an oxide sintered body consisting essentially of a bixbite structure of indium oxide in which gallium atoms are uniformly dissolved and dispersed. Can be manufactured.
- the average particle size of the raw material powder can be measured with a laser diffraction particle size distribution device or the like.
- In 2 O 3 powder and Ga 2 O 3 powder are mixed so that the atomic ratio Ga / (In + Ga) is 0.10 to 0.15.
- the atomic ratio Ga / (Ga + In) is 0.15 or less, it is possible to obtain an oxide sintered body that is substantially made of indium oxide having a Bigsbite structure.
- the raw material powder can be mixed using a wet or dry ball mill, vibration mill, bead mill, or the like.
- a bead mill mixing method is most preferable because the crushing efficiency of the agglomerates is high in a short time and the additive is well dispersed.
- the mixing time is preferably 15 hours or longer, more preferably 19 hours or longer. This is because if the mixing time is insufficient, a crystal structure different from the bixbite structure such as GaInO 3 may be generated in the finally obtained oxide sintered body.
- the mixing time varies depending on the size of the apparatus used and the amount of slurry to be processed, but is adjusted so that the particle size distribution in the slurry is all uniform at 1 ⁇ m or less.
- binder In mixing, an arbitrary amount of binder may be added and mixed at the same time.
- binder polyvinyl alcohol, vinyl acetate, or the like can be used.
- the mixed raw material powder slurry is granulated to form granulated powder, and the granulated powder is molded to produce a molded body.
- Granulation is preferably performed by rapid drying granulation.
- a spray dryer is widely used as an apparatus for rapid drying granulation. Specific drying conditions are determined by various conditions such as the slurry concentration of the slurry to be dried, the temperature of hot air used for drying, and the amount of air. In implementation, it is necessary to obtain optimum conditions in advance. In natural drying, since the sedimentation speed varies depending on the specific gravity difference of the raw material powder, the In 2 O 3 powder and the Ga 2 O 3 powder may be separated, and a uniform granulated powder may not be obtained. If a sintered body is produced using this non-uniform granulated powder, GaInO 3 or the like may be generated inside the sintered body, causing abnormal discharge in sputtering.
- the granulated powder can be molded by a mold press or a cold isostatic press (CIP), and the pressure at the time of molding is, for example, 1.2 ton / cm 2 or more.
- CIP cold isostatic press
- a pressure sintering method such as hot press, oxygen pressurization, hot isostatic pressurization and the like can be employed in addition to the atmospheric pressure sintering method.
- a normal pressure sintering method from the viewpoints of reducing manufacturing cost, possibility of mass production, and easy production of a large sintered body.
- the compact is sintered in an air atmosphere or an oxidizing gas atmosphere, and preferably sintered in an oxidizing gas atmosphere.
- the oxidizing gas atmosphere is preferably an oxygen gas atmosphere.
- the oxygen gas atmosphere is preferably an atmosphere having an oxygen concentration of, for example, 10 to 100 vol%.
- the density of the oxide sintered body can be further increased by introducing an oxygen gas atmosphere in the temperature raising process.
- the firing temperature is 1450 to 1650 ° C.
- the firing time is 10 hours to 50 hours.
- Ga does not dissolve in the indium oxide crystal, and a GaInO 3 phase or the like is formed inside the target, which may cause abnormal discharge.
- the firing temperature exceeds 1650 ° C. or the firing time exceeds 50 hours, the average crystal grain size increases and coarse pores are generated due to remarkable crystal grain growth, resulting in a decrease in the strength of the sintered body or abnormalities. There is a risk of electrical discharge.
- the firing temperature is preferably 1450 to 1600 ° C, more preferably 1480 to 1600 ° C, and particularly preferably 1500 to 1600 ° C.
- the firing time is preferably 10 to 50 hours, more preferably 12 to 40 hours, and particularly preferably 15 to 30 hours.
- the rate of temperature rise during firing is preferably 1 to 15 ° C./min at a temperature range of 500 to 1500 ° C.
- the temperature range of 500 to 1500 ° C. is the temperature range where sintering proceeds most. If the rate of temperature rise in this temperature range is less than 1 ° C./min, crystal grain growth becomes significant, and there is a possibility that densification cannot be achieved. On the other hand, if the rate of temperature rise exceeds 15 ° C./min, the thermal uniformity in the sintering furnace is lowered, so that the amount of shrinkage during sintering is distributed and the sintered body may be cracked.
- the obtained sintered body may be further provided with a reduction step as necessary.
- the reduction step is for making the bulk resistance of the sintered body obtained in the firing step uniform over the entire target.
- Examples of the reduction method that can be applied in the reduction step include reduction treatment with a reducing gas, vacuum firing, and reduction treatment with an inert gas.
- reduction treatment by firing in a reducing gas hydrogen, methane, carbon monoxide, a mixed gas of these gases and oxygen, or the like can be used.
- reduction treatment by firing in an inert gas nitrogen, argon, a mixed gas of these gases and oxygen, or the like can be used.
- the temperature during the reduction treatment is usually 100 to 800 ° C., preferably 200 to 800 ° C.
- the reduction treatment time is usually 0.01 to 10 hours, preferably 0.05 to 5 hours.
- an aqueous solvent is blended with a raw material powder containing a mixed powder of indium oxide powder and gallium oxide powder, and the resulting slurry is mixed for 12 hours or more, followed by solid-liquid separation, drying and granulation. Subsequently, this granulated product is put into a mold and molded, and then the obtained molded product is fired at 1450 to 1650 ° C. for 10 hours or more in an oxygen atmosphere to obtain an oxide sintered body. .
- the sintered body density is 6.0 g / cm 3 or more, the specific resistance is 10 ⁇ cm or less, and the average crystal grain size is 10 ⁇ m or less.
- an oxide sintered body having only a bixbite structure of indium oxide in which gallium atoms are substantially dissolved can be obtained.
- a sputtering target can be obtained by processing the oxide sintered body of the present invention.
- a sputtering target can be obtained by cutting the oxide sintered body of the present invention into a shape suitable for mounting on a sputtering apparatus.
- the sintered body is ground with, for example, a surface grinder to obtain a material having a surface roughness Ra of 5 ⁇ m or less.
- the sputter surface of the target material may be further mirror-finished so that the average surface roughness Ra may be 1000 angstroms or less.
- polishing For this mirror finishing (polishing), a known polishing technique such as mechanical polishing, chemical polishing, and mechanochemical polishing (a combination of mechanical polishing and chemical polishing) can be used. For example, polishing to # 2000 or more with a fixed abrasive polisher (polishing liquid: water) or lapping with loose abrasive lapping (abrasive: SiC paste, etc.), and then lapping by changing the abrasive to diamond paste Can be obtained by: Such a polishing method is not particularly limited.
- the surface of the target material is preferably finished with a diamond grindstone of No. 200 to 10,000, and particularly preferably finished with a diamond grindstone of No. 400 to 5,000. If a diamond grindstone smaller than 200 or larger than 10,000 is used, the target material may be easily broken.
- the target material has a surface roughness Ra of 0.5 ⁇ m or less and has a non-directional ground surface. If Ra is larger than 0.5 ⁇ m or the polished surface has directivity, abnormal discharge may occur or particles may be generated.
- Air blow or running water washing can be used for the cleaning treatment.
- This ultrasonic cleaning is effective by performing multiple oscillations at a frequency of 25 to 300 KHz.
- ultrasonic cleaning is preferably performed by multiplying twelve types of frequencies in 25 KHz increments between frequencies of 25 to 300 KHz.
- the thickness of the target material is usually 2 to 20 mm, preferably 3 to 12 mm, particularly preferably 4 to 6 mm.
- a sputtering target made of the oxide sintered body of the present invention can be obtained by bonding the target material obtained as described above to a backing plate. Further, a plurality of target materials may be attached to one backing plate to substantially form one target.
- the target made of the oxide sintered body of the present invention desirably has a high density, and is preferably 6.2 g / cm 3 or more and 7.1 g / cm 3 or less.
- the oxide semiconductor thin film of the present invention can be obtained by forming a film using the target made of the oxide sintered body of the present invention.
- the film can be formed by, for example, vapor deposition, sputtering, ion plating, pulse laser vapor deposition, or the like.
- gallium is dissolved in the indium oxide crystal, so the lattice constant is reduced, The overlap of 5s orbitals between indium is increased, and an improvement in mobility is expected.
- the oxide semiconductor thin film of the present invention is formed on a substrate by sputtering. Since the oxide sintered body of the present invention has high conductivity, a DC sputtering method having a high film formation rate can be applied. In addition to the DC sputtering method described above, the oxide sintered body of the present invention can be applied to an RF sputtering method, an AC sputtering method, and a pulsed DC sputtering method, and can perform sputtering without abnormal discharge.
- the sputtering gas a mixed gas of argon and an oxidizing gas can be used.
- the oxidizing gas include O 2 , CO 2 , O 3 , and H 2 O.
- the oxygen partial pressure during sputtering film formation is preferably 5% or more and 40% or less.
- a thin film manufactured under a condition where the oxygen partial pressure is less than 5% has conductivity and may be difficult to use as an oxide semiconductor.
- the oxygen partial pressure is 10% or more and 40% or less.
- the substrate temperature during film formation is, for example, 500 ° C. or lower, preferably 10 ° C. or higher and 400 ° C. or lower, more preferably 20 ° C. or higher and 350 ° C. or lower, and particularly preferably 80 ° C. or higher and 300 ° C. or lower.
- the thin film By annealing the thin film on the substrate formed by sputtering, the thin film is crystallized to obtain semiconductor characteristics.
- the oxide semiconductor thin film of the present invention is annealed, Ga is solid-solved in the indium oxide crystal and exhibits a single phase of bixbite.
- the annealing temperature is, for example, 500 ° C. or less, preferably 100 ° C. or more and 500 ° C. or less, more preferably 150 ° C. or more and 400 ° C. or less, and particularly preferably 200 ° C. or more and 350 ° C. or less.
- the heating atmosphere during film formation and annealing is not particularly limited, but an air atmosphere and an oxygen circulation atmosphere are preferable from the viewpoint of carrier controllability.
- a lamp annealing device, a laser annealing device, a thermal plasma device, a hot air heating device, a contact heating device, or the like can be used in the presence or absence of oxygen.
- the oxide semiconductor thin film of the present invention thus obtained is substantially composed of indium oxide having a bixbite structure, and gallium is dissolved in indium oxide, and the atomic ratio Ga / (Ga + In) in the thin film. Can be 0.10 to 0.15.
- the atomic ratio Ga / (Ga + In) is preferably 0.12 to 0.15.
- the oxide semiconductor thin film of the present invention can be used for a thin film transistor and is suitable for a channel layer of the thin film transistor.
- a thin film transistor including the oxide semiconductor thin film of the present invention as a channel layer (hereinafter may be referred to as a thin film transistor of the present invention) may be a channel etch type. Since the oxide semiconductor thin film of the present invention is a crystalline film and has durability, in the manufacture of the thin film transistor of the present invention, a photolithography process for forming a source / drain electrode and a channel part by etching a metal thin film such as Al is also included. It becomes possible.
- the thin film transistor of the present invention may be an etch stopper type.
- the etch stopper can protect the channel portion formed of the semiconductor layer, and a large amount of oxygen is taken into the semiconductor layer during film formation through the etch stopper layer. There is no need to supply oxygen from the outside.
- Example 1-6 An indium oxide powder having an average particle size of 0.98 ⁇ m and a gallium oxide powder having an average particle size of 0.96 ⁇ m are weighed so as to have the atomic ratio Ga / (Ga + In) shown in Table 1, and are uniformly finely pulverized and mixed. A binder was added and granulated. Next, this raw material mixed powder was uniformly filled into a mold, and pressure-molded with a cold press machine at a press pressure of 140 MPa. The molded body thus obtained was fired in a sintering furnace at the firing temperature and firing time shown in Table 1 to produce a sintered body.
- the firing atmosphere was an oxygen atmosphere during the temperature rise, and the other was in the air (atmosphere).
- the average particle size of the raw material oxide powder used was measured with a laser diffraction particle size distribution analyzer SALD-300V (manufactured by Shimadzu Corporation), and the median particle size D50 was used.
- the crystal structure of the obtained sintered body was examined with an X-ray diffraction measurement device (Rigaku Ultimate-III).
- the X-ray charts of the sintered body of Example 1-6 are shown in FIGS. 1-6, respectively.
- the crystal structure can be confirmed with a JCPDS (Joint Committee of Powder Diffraction Standards) card.
- the bixbite structure of indium oxide is JCPDS card no. 06-0416.
- XRD X-ray diffraction measurement
- the density of the obtained sintered body was calculated from the weight and outer dimensions of the sintered body cut into a certain size. Further, the bulk resistance (conductivity) of the obtained sintered body was measured based on a four-probe method (JIS R 1637) using a resistivity meter (Made by Mitsubishi Chemical Corporation, Loresta). The results are shown in Table 1.
- the obtained sintered body was examined for dispersion of Ga by EPMA measurement. As a result, an aggregate of gallium atoms of 1 ⁇ m or more was not observed, and it was found that the sintered body of Example 1-6 was extremely excellent in dispersibility and uniformity.
- the surface of the oxide sintered body obtained in Example 1-6 was ground with a surface grinder, the sides were cut with a diamond cutter, and bonded to a backing plate to obtain a 4-inch ⁇ sputtering target.
- the obtained sputtering target is mounted on a DC sputtering apparatus, and argon is used as a sputtering gas, sputtering pressure is 0.4 Pa, substrate temperature is room temperature, DC output is 400 W, 10 kWh is continuously sputtered, and voltage fluctuation during sputtering.
- argon is used as a sputtering gas
- sputtering pressure is 0.4 Pa
- substrate temperature is room temperature
- DC output 400 W
- 10 kWh is continuously sputtered
- voltage fluctuation during sputtering was stored in a data logger and the presence or absence of abnormal discharge was confirmed.
- Table 1 The presence or absence of the abnormal discharge was performed by monitoring the voltage fluctuation and detecting the abnormal discharge. Specifically, the abnormal discharge was determined when the voltage fluctuation generated during the measurement time of 5 minutes was 10% or more of the steady voltage during the sputtering operation.
- Example 1-6 a mixed gas obtained by adding 3% hydrogen gas to argon gas was used as the atmosphere, and sputtering was performed continuously for 30 hours to check whether nodules were generated. did. As a result, no nodules were observed on the surface of the sputtering target of Example 1-6.
- the sputtering conditions are a sputtering pressure of 0.4 Pa, a DC output of 100 W, a substrate temperature: room temperature, and the hydrogen gas added to the atmosphere gas promotes the generation of nodules.
- nodules For the nodules, a change in the target surface after sputtering was observed 50 times with a stereomicroscope, and a method of measuring the number average of nodules of 20 ⁇ m or more generated in a visual field of 3 mm 2 was adopted. Table 1 shows the number of nodules generated.
- Comparative Example 1-3 Indium oxide powder having an average particle size of 0.98 ⁇ m and gallium oxide powder having an average particle size of 0.96 ⁇ m are weighed so as to have the atomic ratio Ga / (In + Ga) shown in Table 2, and the firing temperature and firing time shown in Table 2 are used. A sintered body and a target were produced and evaluated in the same manner as in Example 1-6 except that firing was performed. The results are shown in Table 2. As can be seen from Table 2, abnormal discharge occurred in the sputtering target of Comparative Example 1-3, and nodules were observed on the target surface.
- FIGS. 7-9 Charts obtained by X-ray diffraction of the sintered body of Comparative Example 1-3 are shown in FIGS. 7-9, respectively.
- a GaInO 3 phase was observed in addition to the bixbite structure in the X-ray diffraction chart.
- the crystal structure can be confirmed with a JCPDS card. If the GaInO 3 phase, the card JCPDSNo. It can be confirmed at 21-0334.
- the crystal structure of the GaInO 3 phase is monoclinic.
- the crystal structure immediately after film formation of the thin film formed on the glass substrate was confirmed by XRD. as a result, A clear diffraction peak was not observed, and it was confirmed to be amorphous.
- the glass substrate on which this thin film was formed was put into a heating furnace heated to 300 ° C. in the air and treated for 1 hour.
- the XRD measurement was performed on the annealed thin film, only the peak of the bixbite structure of indium oxide was observed.
- the crystal structure is JCPDS card no. Can be confirmed at 06-0416.
- the carrier concentration and mobility of the thin film after annealing were evaluated by Hall effect measurement. The carrier concentration was 5.84 ⁇ 10 17 cm ⁇ 3 and the hole mobility was 25.8 cm 2 / Vs. .
- the Hall measuring device and the measurement conditions were as follows: ⁇ Hall measuring device manufactured by Toyo Technica: Resi Test 8310 ⁇ Measurement conditions Measurement temperature: Room temperature (25 °C) Measurement magnetic field: 0.45T Measurement current: 10 ⁇ 12 to 10 ⁇ 4 A Measurement mode: AC magnetic field hall measurement
- the thin film formed on the silicon substrate was formed by placing a metal mask on the conductive silicon substrate, forming a channel portion of L: 200 ⁇ m, W: 1000 ⁇ m, and depositing gold as a source / drain electrode.
- the element was placed in a heating furnace heated to 300 ° C., and a thin film transistor was manufactured by performing treatment for 1 hour.
- the manufactured thin film transistor was evaluated for field effect mobility, on-off ratio, and S value. As a result, it was confirmed that the field effect mobility was 47.6 cm 2 / Vs, the on-off ratio was 8.18 ⁇ 10 7 , a normally-off characteristic was exhibited, and the S value was 1.16. .
- the measurement was performed using a semiconductor parameter analyzer (Keutley 4200) at room temperature, in the air, and in a light-shielding environment.
- the above sputtering is performed at room temperature at a sputtering output of 100 W while evacuating until the back pressure reaches 5 ⁇ 10 ⁇ 4 Pa, adjusting the pressure to 0.4 Pa while flowing argon at 8.5 sccm and oxygen at 1.5 sccm. It was.
- the crystal structure immediately after film formation of the thin film formed on the glass substrate was confirmed by XRD. As a result, a clear diffraction peak was not observed, and it was confirmed to be amorphous.
- the glass substrate on which this thin film was formed was put into a heating furnace heated to 300 ° C. in the air and treated for 1 hour. When the XRD measurement was performed on the annealed thin film, only the peak of the bixbite structure of indium oxide was observed.
- the crystal structure is JCPDS card no. Can be confirmed at 06-0416.
- the carrier concentration and mobility of the thin film after the annealing treatment were evaluated by Hall effect measurement. The carrier concentration was 3.23 ⁇ 10 17 cm ⁇ 3 and the hole mobility was 24.5 cm 2 / Vs. .
- the thin film formed on the silicon substrate was formed by placing a metal mask on the conductive silicon substrate, forming a channel portion of L: 200 ⁇ m, W: 1000 ⁇ m, and depositing gold as a source / drain electrode.
- the element was placed in a heating furnace heated to 300 ° C., and a thin film transistor was manufactured by performing treatment for 1 hour.
- the manufactured thin film transistor was evaluated for field effect mobility, on-off ratio, and S value. As a result, it was confirmed that the field effect mobility was 48.2 cm 2 / Vs, the on-off ratio was 3.67 ⁇ 10 7 , a normally-off characteristic was exhibited, and the S value was 1.23. .
- SiO 2 thermal oxide film
- the sputtering was performed at room temperature at a sputtering output of 100 W while evacuating until the back pressure reached 5 ⁇ 10 ⁇ 4 Pa, adjusting the pressure to 0.4 Pa while flowing argon at 9 sccm and oxygen at 1 sccm.
- the crystal structure immediately after film formation of the thin film formed on the glass substrate was confirmed by XRD. As a result, a diffraction peak was observed, and it was found that it had a bixbite structure of indium oxide and was crystallized.
- the crystal structure is JCPDS card no. Can be confirmed at 06-0416.
- the glass substrate on which this thin film was formed was put into a heating furnace heated to 300 ° C. in the air and treated for 1 hour.
- the carrier concentration and mobility of the thin film after annealing were evaluated by Hall effect measurement, the carrier concentration was 5.3 ⁇ 10 18 cm ⁇ 3 and the hole mobility was 10.2 cm 2 / Vs.
- the thin film after the annealing treatment had a carrier concentration of 10 18 cm ⁇ 3 or more and many oxygen defects, and the hole mobility was inferior to the thin films of Examples 7 and 8.
- the thin film formed on the silicon substrate was formed by placing a metal mask on the conductive silicon substrate, forming a channel portion of L: 200 ⁇ m, W: 1000 ⁇ m, and depositing gold as a source / drain electrode.
- the element was placed in a heating furnace heated to 300 ° C., and a thin film transistor was manufactured by performing treatment for 1 hour.
- the manufactured thin film transistor was evaluated for field effect mobility, on-off ratio, and S value. As a result, it was confirmed that the field-effect mobility was 17.2 cm 2 / Vs, the on-off ratio was 4.5 ⁇ 10 6 , the normally-on characteristics were exhibited, and the S value was 3.27. .
- SiO 2 thermal oxide film
- the sputtering was performed at room temperature at a sputtering output of 100 W while evacuating until the back pressure reached 5 ⁇ 10 ⁇ 4 Pa, adjusting the pressure to 0.4 Pa while flowing argon at 9 sccm and oxygen at 1 sccm.
- the crystal structure immediately after film formation of the thin film formed on the glass substrate was confirmed by XRD. As a result, a diffraction peak was observed, and it was found that it had a bixbite structure of indium oxide and was crystallized.
- the crystal structure is JCPDS card no. Can be confirmed at 06-0416.
- the glass substrate on which this thin film was formed was put into a heating furnace heated to 300 ° C. in the air and treated for 1 hour.
- the carrier concentration and mobility of the annealed thin film were evaluated by Hall effect measurement, the carrier concentration was 9.78 ⁇ 10 18 cm ⁇ 3 and the hole mobility was 11.5 cm 2 / Vs.
- the thin film after the annealing treatment had a carrier concentration of 10 18 cm ⁇ 3 or more and many oxygen defects, and the hole mobility was inferior to the thin films of Examples 7 and 8.
- the thin film formed on the silicon substrate was formed by placing a metal mask on the conductive silicon substrate, forming a channel portion of L: 200 ⁇ m, W: 1000 ⁇ m, and depositing gold as a source / drain electrode.
- the element was placed in a heating furnace heated to 300 ° C., and a thin film transistor was manufactured by performing treatment for 1 hour.
- the manufactured thin film transistor was evaluated for field effect mobility, on-off ratio, and S value.
- the field-effect mobility was 19.5 cm 2 / Vs
- the on-off ratio was 4.64 ⁇ 10 6
- the normally-on characteristic was exhibited
- the S value was confirmed to be 3.88.
- the sputtering target of the present invention can be used for manufacturing thin film transistors and the like.
- the thin film transistor of the present invention can be used for an integrated circuit or the like.
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Abstract
Description
異常放電が頻繁に起きると、プラズマ放電状態が不安定となり、安定した成膜が行われず、膜特性に悪影響を及ぼす。
焼結体中の酸化インジウム成分にガリウム原子及びゲルマニウム原子を置換固溶させ、結晶の最大粒径を5μm以下にすることにより、ノジュールを抑制することが出来る。特許文献4の比較例には、GaのみをドープしたIn2O3ターゲットの製造及びノジュール発生の有無が示されており、ノジュールの発生が顕著であると報告されている。利用した原料粉末の平均粒径が1.8~2μmと大きいだけでなく、焼成時間が6時間と短いために酸化物焼結体中に酸化インジウムのビックスバイト構造以外の相が形成され、ノジュールの発生原因となるおそれがあった。
1.結晶構造が、実質的にビックスバイト構造を示す酸化インジウムからなり、
前記酸化インジウムにガリウム原子が固溶しており、
原子比Ga/(Ga+In)が0.10~0.15である酸化物焼結体。
2.前記原子比Ga/(Ga+In)が0.12~0.15である1に記載の酸化物焼結体。
3.平均粒径が1.2μm以下の酸化インジウム粉末、及び平均粒径が1.2μm以下の酸化ガリウム粉末を、原子比Ga/(Ga+In)が0.10~0.15となるように混合して混合粉末を調製する工程、
前記混合粉末を成形して成形体を製造する工程、及び
前記成形体を1450℃~1650℃で10時間以上焼成する工程を含む1又は2に記載の酸化物焼結体の製造方法。
4.前記焼成を酸化ガス雰囲気中で行なう3に記載の酸化物焼結体の製造方法。
5.1又は2に記載の酸化物焼結体を加工して得られるターゲット。
6.1又は2に記載の酸化物焼結体から得られ、その薄膜中の原子比Ga/(Ga+In)が0.10~0.15である酸化物半導体薄膜。
7.実質的に、結晶構造としてビックスバイト構造を示す酸化インジウムからなる酸化物半導体薄膜であって、前記酸化インジウムにガリウム原子が固溶している6に記載の酸化物半導体薄膜。
8.6又は7に記載の酸化物半導体薄膜がチャネル層である薄膜トランジスタ。
9.8に記載の薄膜トランジスタを備えてなる表示装置。
また、本発明の酸化物焼結体は、ガリウム原子が固溶したビッグスバイト構造の酸化インジウムの単一相からなるので、本発明の酸化物焼結体からなるターゲットのクラック及びノジュールの発生を低減することができる。従って、本発明の酸化物焼結体は、高品質の酸化物半導体薄膜を、効率的に、安価に、且つ省エネルギーで成膜することができる。
上記ビックスバイト構造はX線回折により確認することができる。
また、本発明の酸化物焼結体は、90体積%以上、好ましくは95体積%以上、さらに好ましくは98%体積以上が結晶構造で構成される。好ましくは、本発明の酸化物焼結体は、90体積%以上が結晶構造で構成され、当該結晶構造の90体積%以上がビックスバイト構造を示す酸化インジウムである。
X線回折のピーク解析から体積分率を算出することができる。
上記異常放電の理由としては、ターゲットが不均一で局所的に比抵抗の異なる部分が存在することで、ターゲットを含む放電系のインピーダンスがスパッタリング中に変動してしまうことが推定される。局所的に比抵抗が異なる部分とは、GaInO3等の結晶であり、これら結晶のサイズ及び数密度を小さくすることが異常放電の抑制には効果的である。
例えばICP-AESを用いた分析の場合、溶液試料をネブライザーで霧状にし、アルゴンプラズマ(約6000~8000℃)に導入すると、試料中の元素は熱エネルギーを吸収して励起され、軌道電子が基底状態から高いエネルギー準位の軌道に移る。この軌道電子は10-7~10-8秒程度で、より低いエネルギー準位の軌道に移る。この際にエネルギー差を光として放射し発光する。この光は元素固有の波長(スペクトル線)を示すため、スペクトル線の有無により元素の存在を確認できる(定性分析)。また、それぞれのスペクトル線の大きさ(発光強度)は試料中の元素数に比例するため、既知濃度の標準液と比較することで試料濃度を求めることができる(定量分析)。
このように、定性分析で含有されている元素を特定し、定量分析で含有量を求めることで、各元素の原子比を求めることができる。
密度が6.2g/cm3未満の場合、本発明の酸化物焼結体からなるスパッタリングターゲットの表面が黒化したりし、異常放電を誘発し、スパッタ速度が低下するおそれがある。同密度は、特に好ましくは6.2g/cm3以上7.1g/cm3以下である。
スパッタによってターゲット表面が削られる場合、その削られる速度が結晶面の方向によって異なり、ターゲット表面に凹凸が発生する。この凹凸の大きさは、焼結体中に存在する結晶粒径に依存し、大きい結晶粒径を有する焼結体からなるターゲットでは、その凹凸が大きくなり、その凸部分よりノジュールが発生すると考えられる。
結晶粒は走査型電子顕微鏡(SEM)により観察することができる。
ガリウム原子の集合体の直径はEPMA(電子線マイクロアナライザ)により測定することができる。
尚、酸化物焼結体の比抵抗は、後述する焼結体の製造過程において、窒素等の非酸化性の雰囲気下で加熱する還元処理により低減することができる。
従って、高抵抗相を局所的に含まずに、酸化物焼結体全体の比抵抗が10Ωcm以下であることが重要である。
尚、原料粉末として、酸化インジウム及びガリウム金属を用いる場合、得られる酸化物焼結体中にガリウムの金属粒が存在し、成膜中にターゲット表面の金属粒が溶融していることでターゲットから放出されず、得られる膜の組成と酸化物焼結体の組成とが大きく異なるおそれがある。
尚、上記原料粉末の平均粒径は、レーザー回折式粒度分布装置等で測定することができる。
原子比Ga/(Ga+In)を0.15以下にすることにより、ビッグスバイト構造を示す酸化インジウムから実質的になる酸化物焼結体を得ることができる。
混合にビーズミルを用いる場合は、混合時間は、用いる装置の大きさ及び処理するスラリー量によって異なるが、スラリー中の粒度分布がすべて1μm以下と均一になるように調整する。
バインダーには、ポリビニルアルコール、酢酸ビニル等を用いることができる。
造粒は、急速乾燥造粒を行うと好ましい。急速乾燥造粒するための装置としては、スプレードライヤが広く用いられている。具体的な乾燥条件は、乾燥するスラリーのスラリー濃度、乾燥に用いる熱風温度、風量等の諸条件により決定される。実施に際しては、予め最適条件を求めておくことが必要となる。
尚、自然乾燥では、原料粉末の比重差によって沈降速度が異なるため、In2O3粉末及びGa2O3粉末の分離が起こり、均一な造粒粉が得られなくなるおそれがある。この不均一な造粒粉を用いて焼結体を作製すると、焼結体内部にGaInO3等が生成する場合があり、スパッタリングにおける異常放電の原因となる。
但し、製造コストの低減、大量生産の可能性及び容易に大型の焼結体を製造できるといった観点から、常圧焼結法を採用することが好ましい。
酸化ガス雰囲気は、好ましくは酸素ガス雰囲気である。酸素ガス雰囲気は、酸素濃度が、例えば10~100vol%の雰囲気であるとよい。本発明の酸化物焼結体の作製においては、昇温過程にて酸素ガス雰囲気を導入することで、酸化物焼結体密度をより高くすることができる。
焼成温度が1450℃未満又は焼成時間が10時間未満であると、Gaが酸化インジウム結晶中に固溶せず、GaInO3相等がターゲット内部に形成され、異常放電が起こるおそれがある。一方、焼成温度が1650℃を超えるか、又は焼成時間が50時間を超えると、著しい結晶粒成長により平均結晶粒径の増大、及び粗大空孔の発生をきたし、焼結体強度の低下や異常放電が発生するおそれがある。
焼成温度は、好ましくは1450~1600℃であり、さらに好ましくは1480~1600℃であり、特に好ましくは1500~1600℃である。
焼成時間は、好ましくは10~50時間であり、さらに好ましくは12~40時間であり、特に好ましくは15~30時間である。
500~1500℃の温度範囲は、焼結が最も進行する温度範囲である。この温度範囲での昇温速度が1℃/min未満では、結晶粒成長が著しくなって、高密度化を達成することができないおそれがある。一方、昇温速度が15℃/min超では、焼結炉内の均熱性が低下することで、焼結中の収縮量に分布が生じ、焼結体が割れてしまうおそれがある。
還元性ガス中での焼成による還元処理の場合、水素、メタン、一酸化炭素、又はこれらのガスと酸素との混合ガス等を用いることができる。
不活性ガス中での焼成による還元処理の場合、窒素、アルゴン、又はこれらのガスと酸素との混合ガス等を用いることができる。
上記還元処理時の温度は、通常100~800℃、好ましくは200~800℃である。また、還元処理の時間は、通常0.01~10時間、好ましくは0.05~5時間である。
酸化物焼結体をターゲット素材とするには、該焼結体を、例えば、平面研削盤で研削して表面粗さRaが5μm以下の素材とする。ここで、さらにターゲット素材のスパッタ面に鏡面加工を施して、平均表面粗さRaが1000オングストローム以下としてもよい。この鏡面加工(研磨)は機械的な研磨、化学研磨、メカノケミカル研磨(機械的な研磨と化学研磨の併用)等の、公知の研磨技術を用いることができる。例えば、固定砥粒ポリッシャー(ポリッシュ液:水)で#2000以上にポリッシングしたり、又は遊離砥粒ラップ(研磨材:SiCペースト等)にてラッピング後、研磨材をダイヤモンドペーストに換えてラッピングすることによって得ることができる。このような研磨方法には特に制限はない。
上記成膜は、例えば蒸着法、スパッタリング法、イオンプレーティング法、パルスレーザー蒸着法等により作製できる。本発明の酸化物焼結体を用いてスパッタリング法等に成膜して得られる酸化物半導体薄膜は、ガリウムが酸化インジウム結晶中に固溶しているので、格子定数を小さくし、結晶中のインジウム同士の5s軌道の重なりが大きくなって、移動度の向上が期待される。
本発明の酸化物焼結体は、高い導電性を有することから成膜速度の速いDCスパッタリング法を適用することができる。また、本発明の酸化物焼結体は、上記DCスパッタリング法に加えて、RFスパッタリング法、ACスパッタリング法、パルスDCスパッタリング法にも適用することができ、異常放電のないスパッタリングが可能である。
スパッタリング成膜時の酸素分圧は5%以上40%以下とすることが好ましい。酸素分圧が5%未満の条件で作製した薄膜は導電性を有し、酸化物半導体として利用が困難な場合がある。好ましくは、酸素分圧は10%以上40%以下である。
アニール処理においては、酸素の存在下又は不存在下で、ランプアニール装置、レーザーアニール装置、熱プラズマ装置、熱風加熱装置、接触加熱装置等を用いることができる。
上記原子比Ga/(Ga+In)は、好ましくは0.12~0.15である。
本発明の酸化物半導体薄膜をチャネル層として備える薄膜トランジスタ(以下、本発明の薄膜トランジスタと言う場合がある)は、チャネルエッチ型でもよい。本発明の酸化物半導体薄膜は、結晶膜であり耐久性があるので、本発明の薄膜トランジスタの製造においては、Al等の金属薄膜をエッチングしてソース・ドレイン電極、チャネル部を形成するフォトリソ工程も可能となる。
実施例1-6
平均粒径0.98μmの酸化インジウム粉及び平均粒径0.96μmの酸化ガリウム粉を、表1に示す原子比Ga/(Ga+In)となるように秤量し、均一に微粉砕混合後、成形用バインダーを加えて造粒した。次に、この原料混合粉を金型へ均一に充填しコールドプレス機にてプレス圧140MPaで加圧成形した。このようにして得た成形体を焼結炉により表1に示す焼成温度及び焼成時間で焼成して、焼結体を製造した。
焼成雰囲気は昇温中は酸素雰囲気で、その他は大気中(雰囲気)であり、焼成は、昇温速度1℃/min、降温速度15℃/minで実施した。
尚、用いた原料酸化物粉末の平均粒径は、レーザー回折式粒度分布測定装置SALD-300V(島津製作所製)で測定し、平均粒径はメジアン径D50を採用した。
チャートを分析した結果、実施例1-6の焼結体には酸化インジウムのビックスバイト構造のみが観測された。当該結晶構造は、JCPDS(Joint Committee of Powder Diffraction Standards)カードで確認することが出来る。酸化インジウムのビックスバイト構造は、JCPDSカードNo.06-0416である。
装置:(株)リガク製Ultima-III
X線:Cu-Kα線(波長1.5406Å、グラファイトモノクロメータにて単色化)
2θ-θ反射法、連続スキャン(1.0°/分)
サンプリング間隔:0.02°
スリット DS、SS:2/3°、RS:0.6mm
装置名:JXA-8200(日本電子株式会社製)
加速電圧:15kV
照射電流:50nA
照射時間(1点当り):50mS
尚、上記異常放電の有無は、電圧変動をモニターし異常放電を検出することにより行った。具体的には、5分間の測定時間中に発生する電圧変動がスパッタ運転中の定常電圧の10%以上あった場合を異常放電とした。特にスパッタ運転中の定常電圧が0.1秒間に±10%変動する場合は、スパッタ放電の異常放電であるマイクロアークが発生しており、素子の歩留まりが低下し、量産化に適さないおそれがある。
尚、スパッタ条件は、スパッタ圧0.4Pa、DC出力100W、基板温度:室温であり、雰囲気ガスに添加した水素ガスは、ノジュールの発生を促進するためである。
ノジュールは、スパッタリング後のターゲット表面の変化を実体顕微鏡により50倍に拡大して観察し、視野3mm2中に発生した20μm以上のノジュールについて数平均を計測する方法を採用した。発生したノジュール数を表1に示す。
平均粒径0.98μmの酸化インジウム粉及び平均粒径0.96μmの酸化ガリウム粉を表2に示す原子比Ga/(In+Ga)となるように秤量し、表2に示す焼成温度及び焼成時間で焼成した他は実施例1-6と同様にして焼結体及びターゲットを製造し、評価した。結果を表2に示す。
表2から分かるように、比較例1-3のスパッタリングターゲットおいて異常放電が発生し、ターゲット表面にはノジュールが観測された。
比較例1-3の焼結体では、X線回折チャートにおいてビックスバイト構造の他に、GaInO3相が観測された。当該結晶構造は、JCPDSカードで確認することが出来る。GaInO3相であればカードJCPDSNo.21-0334で確認することができる。また、GaInO3相の結晶構造は単斜晶である。
実施例7
ガラス基板上及び厚み100nmの熱酸化膜(SiO2)付きシリコン基板上にそれぞれ実施例1で得られたターゲット(Ga/(In+Ga)=0.114)を用いてDCマグネトロンスパッタリング法により膜厚50nmの薄膜をそれぞれ成膜した。
上記スパッタリングは、背圧が5×10-4Paとなるまで真空排気したあと、アルゴン9sccm、酸素1sccm流しながら、圧力を0.4Paに調整し、スパッタ出力100Wにて室温で行った。
明瞭な回折ピークは観測されず、アモルファスであることが確認された。この薄膜を形成したガラス基板を空気中、300℃に加熱した加熱炉内に投入し、1時間処理を行った。アニール処理後の薄膜についてXRD測定したところ、酸化インジウムのビックスバイト構造のピークのみが観測された。当該結晶構造は、JCPDSカードNo.06-0416で確認することができる。
また、アニール処理後の薄膜のキャリア濃度及び移動度をHall効果測定で評価したところ、キャリア濃度は5.84×1017cm-3であり、ホール移動度は25.8cm2/Vsであった。
・ホール測定装置
東陽テクニカ製:Resi Test8310
・測定条件
測定温度:室温(25℃)
測定磁場:0.45T
測定電流:10-12~10-4A
測定モード:AC磁場ホール測定
測定は半導体パラメーターアナライザー(ケースレー4200)を用い、室温、大気中、かつ遮光環境下で測定した。
ガラス基板上及び厚み100nmの熱酸化膜(SiO2)付きシリコン基板上にそれぞれ実施例3で得られたターゲット(Ga/(In+Ga)=0.128)を用いてDCマグネトロンスパッタリング法により膜厚50nmの薄膜をそれぞれ成膜した。
上記スパッタリングは、背圧が5×10-4Paとなるまで真空排気したあと、アルゴン8.5sccm、酸素1.5sccm流しながら、圧力を0.4Paに調整し、スパッタ出力100Wにて室温で行った。
また、アニール処理後の薄膜のキャリア濃度及び移動度をHall効果測定で評価したところ、キャリア濃度は3.23×1017cm-3であり、ホール移動度は24.5cm2/Vsであった。
酸化インジウム粉及び酸化ガリウム粉を原子比Ga/(In+Ga)=0.029となるように秤量した他は、実施例1と同様にして焼結体を製造し、ターゲットを製造した。
ガラス基板上及び厚み100nmの熱酸化膜(SiO2)付きシリコン基板上にそれぞれ製造したターゲット(Ga/(In+Ga)=0.029)を用いてDCマグネトロンスパッタリング法により膜厚50nmの薄膜をそれぞれ成膜した。
上記スパッタリングは、背圧が5×10-4Paとなるまで真空排気したあと、アルゴン9sccm、酸素1sccm流しながら、圧力を0.4Paに調整し、スパッタ出力100Wにて室温で行った。
アニール処理後の薄膜のキャリア濃度及び移動度をHall効果測定で評価したところ、キャリア濃度は5.3×1018cm-3であり、ホール移動度は10.2cm2/Vsであった。アニール処理後の薄膜は、キャリア濃度が1018cm-3以上で酸素欠陥が多い薄膜となり、ホール移動度も実施例7及び8の薄膜と比較して劣るものであった。
酸化インジウム粉及び酸化ガリウム粉を原子比Ga/(In+Ga)=0.015となるように秤量した他は、実施例1と同様にして焼結体を製造し、ターゲットを製造した。
ガラス基板上及び厚み100nmの熱酸化膜(SiO2)付きシリコン基板上にそれぞれ製造したターゲット(Ga/(In+Ga)=0.015)を用いてDCマグネトロンスパッタリング法により膜厚50nmの薄膜をそれぞれ成膜した。
上記スパッタリングは、背圧が5×10-4Paとなるまで真空排気したあと、アルゴン9sccm、酸素1sccm流しながら、圧力を0.4Paに調整し、スパッタ出力100Wにて室温で行った。
アニール処理後の薄膜のキャリア濃度及び移動度をHall効果測定で評価したところ、キャリア濃度は9.78×1018cm-3であり、ホール移動度は11.5cm2/Vsであった。アニール処理後の薄膜は、キャリア濃度が1018cm-3以上で酸素欠陥が多い薄膜となり、ホール移動度も実施例7及び8の薄膜と比較して劣るものであった。
この明細書に記載の文献の内容を全てここに援用する。
Claims (9)
- 結晶構造が、実質的にビックスバイト構造を示す酸化インジウムからなり、
前記酸化インジウムにガリウム原子が固溶しており、
原子比Ga/(Ga+In)が0.10~0.15である酸化物焼結体。 - 前記原子比Ga/(Ga+In)が0.12~0.15である請求項1に記載の酸化物焼結体。
- 平均粒径が1.2μm以下の酸化インジウム粉末、及び平均粒径が1.2μm以下の酸化ガリウム粉末を、原子比Ga/(Ga+In)が0.10~0.15となるように混合して混合粉末を調製する工程、
前記混合粉末を成形して成形体を製造する工程、及び
前記成形体を1450℃~1650℃で10時間以上焼成する工程を含む請求項1又は2に記載の酸化物焼結体の製造方法。 - 前記焼成を酸化ガス雰囲気中で行なう請求項3に記載の酸化物焼結体の製造方法。
- 請求項1又は2に記載の酸化物焼結体を加工して得られるターゲット。
- 請求項1又は2に記載の酸化物焼結体から得られ、その薄膜中の原子比Ga/(Ga+In)が0.10~0.15である酸化物半導体薄膜。
- 実質的に、結晶構造としてビックスバイト構造を示す酸化インジウムからなる酸化物半導体薄膜であって、前記酸化インジウムにガリウム原子が固溶している請求項6に記載の酸化物半導体薄膜。
- 請求項6又は7に記載の酸化物半導体薄膜がチャネル層である薄膜トランジスタ。
- 請求項8に記載の薄膜トランジスタを備えてなる表示装置。
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JP2013067855A (ja) * | 2011-09-06 | 2013-04-18 | Idemitsu Kosan Co Ltd | スパッタリングターゲット |
WO2015137274A1 (ja) * | 2014-03-14 | 2015-09-17 | 住友金属鉱山株式会社 | 酸化物焼結体、スパッタリング用ターゲット、及びそれを用いて得られる酸化物半導体薄膜 |
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JP5966840B2 (ja) | 2012-10-11 | 2016-08-10 | 住友金属鉱山株式会社 | 酸化物半導体薄膜および薄膜トランジスタ |
JP6107085B2 (ja) * | 2012-11-22 | 2017-04-05 | 住友金属鉱山株式会社 | 酸化物半導体薄膜および薄膜トランジスタ |
JP5883990B2 (ja) * | 2013-03-29 | 2016-03-15 | Jx金属株式会社 | Igzoスパッタリングターゲット |
CN105393360B (zh) * | 2013-07-16 | 2018-11-23 | 住友金属矿山株式会社 | 氧化物半导体薄膜和薄膜晶体管 |
CN107001144A (zh) * | 2014-11-25 | 2017-08-01 | 住友金属矿山株式会社 | 氧化物烧结体、溅射用靶、以及使用其得到的氧化物半导体薄膜 |
JP2017154910A (ja) * | 2016-02-29 | 2017-09-07 | 住友金属鉱山株式会社 | 酸化物焼結体及びスパッタリング用ターゲット |
KR102543783B1 (ko) | 2017-02-01 | 2023-06-15 | 이데미쓰 고산 가부시키가이샤 | 비정질 산화물 반도체막, 산화물 소결체, 및 박막 트랜지스터 |
KR102598375B1 (ko) | 2018-08-01 | 2023-11-06 | 이데미쓰 고산 가부시키가이샤 | 결정 구조 화합물, 산화물 소결체, 스퍼터링 타깃, 결정질 산화물 박막, 아모르퍼스 산화물 박막, 박막 트랜지스터, 및 전자 기기 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006165530A (ja) * | 2004-11-10 | 2006-06-22 | Canon Inc | センサ及び非平面撮像装置 |
WO2009008297A1 (ja) * | 2007-07-06 | 2009-01-15 | Sumitomo Metal Mining Co., Ltd. | 酸化物焼結体とその製造方法、ターゲット、及びそれを用いて得られる透明導電膜ならびに透明導電性基材 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3947575B2 (ja) | 1994-06-10 | 2007-07-25 | Hoya株式会社 | 導電性酸化物およびそれを用いた電極 |
JPH09259640A (ja) * | 1996-03-25 | 1997-10-03 | Uchitsugu Minami | 透明導電膜 |
EP2278041B1 (en) * | 2001-08-02 | 2012-05-23 | Idemitsu Kosan Co., Ltd. | Sputtering target and transparent conductive film obtainable by the target |
US7211825B2 (en) * | 2004-06-14 | 2007-05-01 | Yi-Chi Shih | Indium oxide-based thin film transistors and circuits |
JP5058469B2 (ja) | 2005-09-06 | 2012-10-24 | キヤノン株式会社 | スパッタリングターゲットおよび該ターゲットを用いた薄膜の形成方法 |
JP4846726B2 (ja) * | 2005-09-20 | 2011-12-28 | 出光興産株式会社 | スパッタリングターゲット、透明導電膜及び透明電極 |
JP4805648B2 (ja) * | 2005-10-19 | 2011-11-02 | 出光興産株式会社 | 半導体薄膜及びその製造方法 |
US20090090914A1 (en) * | 2005-11-18 | 2009-04-09 | Koki Yano | Semiconductor thin film, method for producing the same, and thin film transistor |
WO2008114588A1 (ja) * | 2007-03-20 | 2008-09-25 | Idemitsu Kosan Co., Ltd. | スパッタリングターゲット、酸化物半導体膜及び半導体デバイス |
US8148245B2 (en) | 2007-12-27 | 2012-04-03 | Jx Nippon Mining & Metals Corporation | Method for producing a-IGZO oxide thin film |
WO2009128424A1 (ja) * | 2008-04-16 | 2009-10-22 | 住友金属鉱山株式会社 | 薄膜トランジスタ型基板、薄膜トランジスタ型液晶表示装置および薄膜トランジスタ型基板の製造方法 |
-
2010
- 2010-01-15 JP JP2010006831A patent/JP5437825B2/ja active Active
-
2011
- 2011-01-14 KR KR1020127018153A patent/KR20120123322A/ko active Application Filing
- 2011-01-14 KR KR1020177020621A patent/KR102001747B1/ko active IP Right Grant
- 2011-01-14 WO PCT/JP2011/000169 patent/WO2011086940A1/ja active Application Filing
- 2011-01-14 TW TW100101510A patent/TWI496758B/zh active
- 2011-01-14 EP EP11732812.0A patent/EP2524905A4/en not_active Withdrawn
- 2011-01-14 CN CN201180004849.0A patent/CN102652119B/zh active Active
- 2011-01-14 US US13/522,198 patent/US20120292617A1/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006165530A (ja) * | 2004-11-10 | 2006-06-22 | Canon Inc | センサ及び非平面撮像装置 |
WO2009008297A1 (ja) * | 2007-07-06 | 2009-01-15 | Sumitomo Metal Mining Co., Ltd. | 酸化物焼結体とその製造方法、ターゲット、及びそれを用いて得られる透明導電膜ならびに透明導電性基材 |
Non-Patent Citations (1)
Title |
---|
MINAMI, T ET AL.: "Preparation of highly transparent and conducting Ga203-In203 films by direct current magnetron sputtering", JOURNAL OF VACUUM SCIENCE & TECHNOLOGY, vol. A 15, no. 3, 1997, pages 958 - 962, XP002599388 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013067855A (ja) * | 2011-09-06 | 2013-04-18 | Idemitsu Kosan Co Ltd | スパッタリングターゲット |
US9767998B2 (en) | 2011-09-06 | 2017-09-19 | Idemitsu Kosan Co., Ltd. | Sputtering target |
WO2015137274A1 (ja) * | 2014-03-14 | 2015-09-17 | 住友金属鉱山株式会社 | 酸化物焼結体、スパッタリング用ターゲット、及びそれを用いて得られる酸化物半導体薄膜 |
CN106103379A (zh) * | 2014-03-14 | 2016-11-09 | 住友金属矿山株式会社 | 氧化物烧结体、溅射靶以及使用该溅射靶而获得的氧化物半导体薄膜 |
JPWO2015137274A1 (ja) * | 2014-03-14 | 2017-04-06 | 住友金属鉱山株式会社 | 酸化物焼結体、スパッタリング用ターゲット、及びそれを用いて得られる酸化物半導体薄膜 |
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