TWI378149B - - Google Patents

Description

1378149 IX. OBJECTS OF THE INVENTION The present invention relates to a Sn02-based sputtering target and a sputtering film produced using the same, and specifically relates to various uses in flat panel displays, touch panels, solar cells, and the like. It is used in Sn02-based sputter targets and their sputter films for ensuring various functions of transparent electrodes, anti-charge, electromagnetic glass shielding, gas barriers, and heat line reflection.

[Prior Art] In recent years, the Sn 2 film has been used for a wide range of applications such as flat panel displays, touch panels, and solar cells. Industrially, the Sn02-based film is produced by a spray method or a CVD method as a mainstream. However, these methods are not suitable for uniformizing the film thickness over a large area, and it is also difficult to control the film forming process, and it is a high-temperature or chlorine-based gas which can generate a pollutant during film formation, and thus it is required not to New manufacturing methods for these shortcomings.

On the other hand, the production of a Sn02-based film by sputtering is also attempted, and as a sputtering target for this purpose, a target of Sn02-Sb203 to which Sb203 is added has been industrially applied. However, the sputtering film of Sn02-Sb203 used for such a target has a lower resistivity due to heat treatment, and if heat is received in an uneven temperature distribution, distribution of the resistivity 値 is likely to occur. Therefore, heat resistance is poor. In addition, the Sn02-Sb203 sputter film is heat-treated at a temperature of 200 ° C or higher to reduce the resistance, and thus is not suitable for heat-treated plastics and the like for low heat resistance of substrates (for example, not 9 ηηΩ · cm) The production of the film is difficult. Again, -4- 1378149

Sn〇2-Sb2〇3粑 is mechanically strong (bending strength), so cracks or cracks are likely to occur during operation. As a result, abnormal discharge occurs during sputtering and adversely affects the performance of sputtering. . In addition, Sb203 is the object specified in the second paragraph of the toxic and genre designation order, and is therefore used in the safety and environmental aspects of the target. A high performance Sn02-based sputtering target that is required to replace the Sn02-Sb203 target.

As a Sn02-based material other than the Sn02-Sb203 system, for example, the following proposals are proposed. At least one selected from the group consisting of Al, Si, Nb, Ta, and Y is known, and the total amount of addition is 20% by weight or less in terms of oxide, and Sn02 having a resistivity of 1 x 107 Ω · cm A sintered body (for example, refer to JP-A-2000-281431). In addition, a method of forming a low-resistance transparent conductive film using an oxide material by adding 0.5 to 10% by weight of cerium oxide to a film-forming composition obtained by separately adding tin oxide (for example, refer to Japan's special fair) Bulletin 5 - 42763). In addition, a sintered body containing tin oxide of 0.5% by weight or less in an oxide such as ruthenium or ruthenium is known (for example, refer to Japanese Laid-Open Patent Publication No. Hei. Further, a substrate for a transparent touch panel in which a metal oxide transparent conductive film containing tin and ytterbium or ytterbium is formed on the surface of a transparent substrate is known (for example, see JP-A-2002-73280). However, in any of these documents, there is no indication that the Sn02-based sputtering target having a low film resistivity can be realized without reducing the abnormal discharge in the sputtering process. [Inventive content] -5 - 1378149 The inventor of the present invention In this case, for the Ta205-Nb205-Sn02 sintered body, by adding the amount of Ta205 to 1.5 to 3.5% by weight, and by adding the amount of Nb205 to 0.25 to 2% by mass, the bending strength is excellent, and the essence is obtained. The Sn02-based sintered body having no condensed phase, and when used as a sputtering target, it is possible to obtain an abnormal discharge during sputtering, and to have a low film resistivity even without heat treatment, and further heating thereafter The treatment has a small change in resistivity and excellent thermal resistance.

The knowledge of the membrane. Therefore, an object of the present invention is to provide a low film resistivity which can be obtained while reducing the abnormal discharge during sputtering, and which has a small change in resistivity after heat treatment, and which is excellent in heat resistance. The Sputtered Film is excellent in the flexural strength and has substantially no condensed phase of the Sn02-based sputtering target. That is, a Sn02-based sputtering target according to the present invention is characterized in that it contains 1.5 to 3.5% by mass of Ta205, and 0.25 to 2% by mass of Nb205, and as a remaining portion of Sn02 and unavoidable impurities. It is composed of a sintered body. Further, a Sn〇2 sputtering film according to the present invention and a sputtering film produced by sputtering using the above-described sputter target are characterized in that the film contains 1.5 to 3.5% by mass of Ta2〇2, and 〇 25 to 2% by mass of Nb2〇5' and as the remaining part of Sn02 and unavoidable impurities. [Embodiment] Sn02 sputtering target

1378149 A Sn02-based sputtering target according to the present invention is formed by containing and remaining Sn02 and unavoidable impurities. In such a Ta205-Nb205-Sn02 sintered body, by massing 1.5 to 3.5% by mass and Nb 205 to 2% by mass, a substantially Sn02-based sintered body having excellent bending strength can be obtained. Further, in the case of the Sn02-based sintered body, the abnormal discharge during sputtering can be reduced, and the heat treatment also has a low change in film resistivity and a heat-resistant film. In this way, the low film resistance can be obtained without heat treatment, and the low resistance (for example, less than 9 m Ω · cm) for a substrate such as plastic which is not suitable for heat treatment can be obtained, and the change in the resistivity of the subsequent heat treatment is small, and the temperature distribution is small. The heat is received, and it is not easy to produce a heat resistance coefficient excellent in heat resistance. This heat resistance is excellent in the process of forming a transparent conductive medium, and exposure to a (PDP) process of 500 ° C to 600 ° C. In addition, the sputtering can be reduced, and a stable magnetron discharge can be performed for a long time, and a sputtering film can be used. Further, since the safety of the object such as Sb2〇3 is not used, it is safe and environmentally preferable. According to a preferred embodiment of the present invention, the mass % of Nb2〇5 is preferable. If it is within this range, the discharge can be sufficiently reduced, and a lower film resistivity (for example) can be obtained. Further, according to a more preferred aspect of the present invention, Ta205 is 3.0% by mass, and the content of Nb205 is 0.25.

Ta2〇5, Nb2〇5, the sintered body is formed by adding Ta205 to the amount of 0.25, and there is no condensed phase, and the sputtering target is used as a sputtering target, even if there is no sputtering coefficient excellent in the sputtering coefficient. The film having a low heat-resistant temperature has a uneven distribution of ruthenium even in the sputtering film. Therefore, the abnormal discharge in the ammonium of the paste display plate having the baking temperature after the electric film produces excellent characteristics, so that an equivalent amount of 0.25 to 1 in the low sputtering is less than 6 m Ω. The content of the cm is 1.5. To 0.75 mass% of 1378149

Nb205 is preferred. In this range, the abnormal discharge and the low film resistivity described above are reduced, and the change in the resistance constant by the heat treatment can be made extremely small, and a sputtering film having remarkably excellent heat resistance can be obtained. According to a preferred embodiment of the present invention, the sputtering target according to the present invention is preferably agglomerated phase formed by Ta which does not substantially contain a Feret's diameter of 10 μm or more. Thereby, the abnormal discharge in the sputtering can be sufficiently reduced, and a sputtering film having excellent characteristics can be obtained.

According to a preferred embodiment of the present invention, it has a bending strength of l 〇 kgf/mm 2 or more, preferably 12 kgf / mm 2 or more, measured in accordance with JIS-R-1601. Therefore, when the target is mounted on the sputtering cathode and bolted, or subjected to an instantaneous pressure shock in the vacuum venting apparatus, or when thermal shock is applied by applying the sputtering power, Cracks or cracks are hard to occur, and as a result, abnormal discharge in sputtering is sufficiently reduced, and a sputtering film having excellent characteristics can be obtained.

Method for Producing Sn02-Based Sputtering Target The method for producing a Sn02-based sputtering target according to the present invention is not particularly limited, but can be carried out in accordance with the preferred embodiment shown below. That is, according to a preferred aspect of the present invention, first, Sn02 is used as a main component, and Ta205 is contained in an amount of 1.5 to 3.5% by mass, and Nb205 is contained in an amount of 0.25 to 2% by mass of an unsintered formed body. In the present invention, the unsintered molded body may be formed by molding any of the raw material powders having the above-described composition by any method, for example, by mixing Sn02 powder 'Nb205 powder and Ta205 powder to satisfy the composition ratio of the above composition. The raw material powder can be produced by forming the 1378149 raw material powder.

According to a preferred embodiment of the present invention, the molded body of the unsintered body of the raw material powder is preferably a binder which is added to the raw material powder to easily impart a desired shape. As such a binder, a known binder which does not disappear or scatter by heating is not limited, and an aqueous polyvinyl alcohol solution or the like can be used. The drying and heating method is not limited, and it is preferred to carry out the degreasing by first drying at 50 to 130 ° C for 5 to 30 hours, followed by heating at 500 to 800 ° C for 6 to 24 hours. According to a preferred embodiment of the present invention, the unsintered shaped body prepared as described above is sintered at 1,500 to 1,650 °C. By performing sintering in this temperature range, liquid phase sintering is sufficiently performed to increase the sintered density, and the sputtering film can increase the transmittance when the resistivity 値 is the smallest, and prevent the melting of Sn02 and facilitate the sintering in a desired form. The preferred sintering temperature is 1 5 50 to 1 600 ° C in this temperature range, which can reduce the temperature difference inside the sintered body, thereby effectively preventing the bending of the sintered body and improving the productivity. . In a preferred aspect of the invention, sintering is preferably carried out for 2 to 20 hours, more preferably 3 to 12 hours, and most preferably 4 to 8 hours. If it is within this range, power consumption can be suppressed, and sintering can be sufficiently performed while ensuring high productivity. In accordance with a preferred embodiment of the present invention, sintering is preferably carried out in an oxygen-containing atmosphere in order to ensure a high sintered density, for example, under an oxygen-pressurized atmosphere, an oxygen atmosphere, or a large atmosphere. 1378149

Sn02 system sputtering film

The sputter film of the present invention is a sputter film produced by sputtering using the above-described sputtering target of the present invention. The sputter film may have the same composition as the sputtering target, and specifically contains 1.5 to 3.5% by mass of Ta205 and 0.25 to 2% by mass of Nb205, and the remaining portion of Sn02 and unavoidable impurities. According to a preferred embodiment of the present invention, as in the case of the sputtering target, the content of Nb205 is preferably 0.25 to 1% by mass, more preferably the content of Ta205 is 1-5 to 3.0% by mass, and the content of Nb2〇5 is contained. The amount is 0.25 to 0.75 mass% of Nb205. According to a preferred embodiment of the present invention, the sputtering film has a resistivity of less than 9.0 m Ω · cm, more preferably less than 6. ιηιΩ · cm, and most preferably has a resistivity of less than 5. ΟηηΩ · cm. . Thereby, high conductivity can be achieved in the sputter film. These low film resistivities are preferably achieved without heat treatment, but the present invention is not limited thereto, and the film resistivity may be imparted to the sputter film by heat treatment. According to a preferred embodiment of the present invention, the coefficient of change of the resistivity of the sputtered film after the heat treatment in the heat treatment at the time of the sputter film is preferably 10% or less, more preferably 10% or less, of the sputtered sputter film before the heat treatment. Good is 9% or less. As described above, in the case of the rate of change of the low resistivity before and after the heat treatment, even if heat is absorbed by the uneven temperature distribution, the distribution of the resistivity 値 is hard to occur, and thus the heat resistance is excellent. This heat resistance is a process of baking a medium after forming a transparent conductive film, and is extremely advantageous in the process of a plasma display panel (PDP) exposed to a temperature of 500 ° C to 600 ° C. -10- 1378149

The sputter film according to the present invention is a magnetron sputtering apparatus in which the sputtering target of the present invention is disposed, and can be produced by sputtering. The sputtering operation is performed in accordance with well-known conditions (e.g., reaching vacuum degree, sputtering pressure, oxygen partial pressure, on-power, substrate temperature, etc.) generally employed in magnetron sputtering. Further, the preferred degree of arrival vacuum is from 1 χ 10 _ 5 to 1 x 10 〇 _ 3 Pa. Further, a preferred sputtering pressure (Ar pressure in terms of nitrogen gas) is 0.1 to 1.0 Oa. The preferred oxygen partial pressure is lxl (T4 to 5xl (T2Pae preferably has a turn-on power of 0.5 to 1 OW/cm2. A preferred substrate temperature is 0 to 300 ° C. According to this sputtering, one side is effectively effective The arc discharge in sputtering is reduced, and a sputtering film having uniform film thickness is efficiently formed. According to a preferred embodiment of the present invention, sputtering is performed using a cumulative power density of 1 to 50 W·hr/cm 2 . The number of abnormal discharges is preferably 30 or less, more preferably 15 or less. Thus, the number of low abnormal discharges is achieved by using the sputtering target according to the present invention, whereby magnetization can be performed stably for a long time. Tube discharge produces a sputtered film with excellent properties.

EXAMPLES Examples 1 to 2 6 (1) Preparation of Sputtering Targets First, the following three types of raw material powders were prepared.

Sn02 powder: purity 99.9% (3Ν), average particle size 2.5~4_5 μιη, specific surface area 3.0~5.5m2/g

Ta2〇5 powder: purity 99.9% (3Ν), average particle size 〇.6~0·8 μιη, specific surface area 2.0~3.1m2/g -11 - 1378149

Nb205 powder: purity 99.9% (3N), average particle size 0.6~1·〇 μιη, specific surface area 2.1~2.7m2/g

For each example, the composition shown in Tables 1 and 2 was used, and the above-mentioned three types of raw material powders were mixed by a ball mill for 21 hours. An aqueous solution of polyvinyl alcohol was added to the mixed powder, and it was filled in a metal mold having a size of 400 x 800 mm, and subjected to press molding at a pressure of 800 kgf/cm2. The molded body was dried at 800 ° C for 12 hours, and the dried body was fired in an oxygen atmosphere at a firing temperature of 1,600 ° C for 8 hours to obtain a sintered body. At this time, the temperature rise rate is controlled to 400 ° C / hr, and the temperature drop rate is controlled to i 〇〇 ° c / hr. The obtained sintered body was processed into a diameter of 1 52 mm and a thickness of 5 mm to obtain a Sn02-based sputtering target. (2) Evaluation Various evaluation tests shown below were carried out for the obtained sputtering target. Evaluation 1: Measurement of resistivity of sputtered film before heat treatment The spoiler target metal obtained in Examples 1 to 26 was adhered to a mat of oxygen-free copper. At this time, the center line average roughness Ra of the sputtering target of the sputtering target is measured to be 0.7 to 1.1 cm. Further, the composition ratio of the ICP analysis using the processed material generated during the processing of each sputtering target is the same as the composition of the mixed powder used as the raw material. Further, for each of the sputtering targets bonded by the metal, magnetron sputtering using a DC power source was performed under the following conditions, and sputtering was performed on the alkali-free glass substrate. -12- 1378149

Cathode: Strong magnetic field Magnetic circuit Sputter chamber arrival pressure: <lxl〇“Pa Substrate temperature: room temperature (no heating) Introduced oxygen partial pressure: 〇.67Pa Introduced oxygen partial pressure: 〇~5xl (T2Pa DC applied power: 3 00W

Film thickness: 1 50 nm Substrate: Alkali-free glass A sheet resistance was measured by a four-probe method using a sheet resistance measuring instrument (MCP-TP06P, manufactured by Dai-Asian Instruments Co., Ltd.) for the sputtering film thus obtained. Further, the film resistivity (ηιΩ · cm) was calculated by multiplying the film thickness measured by a stylus type surface shape measuring device (Dektak 6M, manufactured by ULVAC Co., Ltd.) on the obtained sheet resistance 値. The minimum resistivity of the above-mentioned introduced oxygen gas is shown in the resistance coefficient column before heat treatment in Tables 1 and 2. As shown in Tables 1 and 2, it is understood that the present invention is satisfied.

The composition of the sputtering target has a particularly low film resistivity as compared with many examples outside the scope of the present invention. Evaluation 2: Evaluation of the electric resistivity of the sputtered film after the heat treatment For the examples 1 to 26, in the evaluation 1 by sputtering, the resistivity was minimized before the heat treatment, and the heat treatment was performed at 5 5 Ot in the air atmosphere. hour. The sheet resistance was measured in the same manner as in Evaluation ,, and the film thickness measured in the evaluation 1 was multiplied to calculate the electric resistance coefficient. Further, the rate of change of the resistivity before and after the heat treatment was calculated according to the following formula. -13- 1378149 Rate of change (%) = { 1 - (resistance coefficient after heat treatment) / (resistance coefficient before heat treatment)} XI 〇〇 The result is as shown in Table 1, and sputtering which satisfies the composition of the present invention is known. The targets all have a low rate of change in membrane resistivity.

Evaluation 3: Evaluation of the condensed phase of the sintered body For the examples 1 to 26, the honing of the sintered body using the #2000 sandpaper was performed by honing to generate the fracture surface of the sintered body which was produced during the processing of the sputtering target until In the mirror state, a composition surface scanning image of molybdenum was obtained using SEM-EDS (JSM-63 80A, manufactured by JEOL Co., Ltd.). In the binary image processing, the image processing software (particle analysis III, manufactured by Akeisoft Co., Ltd.) was used to calculate the Feret diameter, and it was judged whether or not there was a Ta aggregation of 10 μm or more and is shown in Tables 1 and 2. Further, Fig. 1 shows a macroscopic surface scan image obtained by the sintered body of Example 4, and Fig. 2 shows a molybdenum composition surface scan image obtained for the sintered body of Example 19 (comparative). As is apparent from Tables 1 and 2, the sputtering target satisfying the composition of the present invention is as shown in Fig. 1, and no condensed phase of ruthenium is observed, but in many cases other than the scope of the present invention, Fig. 2 shows a large condensed phase observed as a white block portion. Evaluation 4: Evaluation of the flexural strength of the sintered body For the examples 1 to 26, the yield test was produced according to JIS-R-1601 using a bending tester (automatic chart, manufactured by Nipponshima-14-1378149, manufactured by Tsusho Co., Ltd.). The bending strength of the sintered body in which the target is processed. As a result, as shown in Tables 1 and 2, it is understood that the sputtering target which satisfies the composition of the present invention has a particularly high bending strength as compared with many examples outside the scope of the present invention. Evaluation 5: Evaluation of abnormal discharge in sputtering

Using the sputtering targets of Example 26, the cumulative number of abnormal discharges occurring in the continuous sputtering discharge of the cumulative power density of 2 to 50 W · hr/cm 2 was counted under the following sputtering conditions. Further, the count of the abnormal discharge was performed using an arc counter-Arc Monitor manufactured by Landmark. As a result, as shown in Tables 1 and 2, it is understood that the number of abnormal discharges is particularly small as compared with many examples of the sputtering target which satisfy the composition of the present invention.

Cathode: Strong magnetic field Magnetic circuit Sputter chamber arrival pressure: lxl〇_4Pa Substrate temperature: room temperature (no heating) Introduced argon partial pressure: 〇.67Pa Introduced oxygen partial pressure: 1.5xlO_2Pa DC applied power: 3 00W -15- 1378149

〔一-嫩〕 Abnormal release ® (次) υο cn r-^ Ό <N f _ 卜〇\一— O cs <N Ol <N 00 CN Anti-arm strength (kgf/mm2) Bu inch oo 〇 \ c^iv〇in m vS Os M , Os ιτί OO CO oo cn VO oo vd CNJ inch inch v〇<N (> I condensed phase reading 璀鹿葚璀 m reading 壊鹿璀 m film resistivity change Rate (%) 〇〇Os VO 00 os CO ON 00 〇6 (N rj; ? cn cn oo inch σ\ tT) CN Ό r〇1—H OO ζΐ m ^ 剧盛 G _ _gt; g sharp w inch Cn oo rn CN cn cn ON cn (N Tf to — oo cn — rn l〇一CN o 鲣^ •N镰! Rent 1筚? 魑G G _日壊w ΓΟ (N ^f vn CO 00 rn寸 inch a\ »/S oo inch 00 inch oo oo 00 inch · oo composition * Nb205 (mass%) 〇r·^ CN oo 〇<N (N 〇o CN (N o __h <N Ta2〇s ( Mass %) tn (N CN (N CN cn m cn m rn ir > rn rn CN fO 寸 v〇 oo GTs m case 10 cases 11 cases 12 cases 13 cases 14 . 3⁄4 carbonyl 轵 tide l ^ lf ^ ^ Ous φ§δ盘鞣:, -16- 1378149

[CNIS abnormal discharge (times) 〇〇〇1 524 8546 2345 卜\η 〇\ 1985 2258 1623 15998 12556 16987 Bending strength I (kgf/mm2) 15.7 16.2 16.2 15.9 12.5 j 13.6 OS m ν〇00 (N VO m VO ΙΟ \ό — (Ν v〇in condensed phase I_ 挞揉揉薜揉薜揉lian I 1 (change rate of membrane resistivity (%) 20.9 23.3 45.7 54.1 36.8 44.6 Bu 18.2 41.3 23.8 41.2 41.6 r—^ (Ν ON 67.5 85.5 m ^ 鹚筚? _盛G 豳_> g more w divination (N 〇\ VO 00 00 inch · inch (N — — inch 00 — Ο ιή CS in <Ν — OS cn OO inch• N sharp! nm healed _ ε 璀w CS inch inch cO 00 as cn cn vd 00 σ\ οό m CN mm composition * Nb205 (mass%) in <N (N m CN ir> oi 〇0.25 (S ο ο Ο 99wt%Sn〇2-1 wt%Sb2〇3 97wt%Sn〇2-3wt%Sb2〇3 95wt%Sn〇2-5wt%Sb2〇3 丨Ta2〇5 i (% by mass) CN m cn inch inch (Ν m \Τ) rn Example 15 (comparative) Example (comparative) Example 17 (comparative) Example 18 (comparative) Example 19 (comparative) Example 20 (comparative) Example 21 (comparative) Example 22 (comparative) Example 23 (comparative) Example 24 (comparative) Example 25 (comparative) Example 26 (Comparative) Example 27 (Comparative) Example 28 (Comparative) Example 29 (Comparative) 鲰漶轵锴Ikik^^ocs butterfly Φ镝 cone ii :, -17-

1378149 Examples 27 to 29 First, the following two types of raw material powders were prepared. 311〇2 powder: purity 99.9% (3]^), average particle size 2.5~4.5, specific surface area 3.0~5.5m2/g

Sb203 powder: purity 99.9% (3N), average particle diameter 0.6 to μηη For each of the above examples, the above two types of raw material powders were mixed in a ball mill for 21 hours. An aqueous solution of an enol was added to the mixture, and it was filled with a film of a size of 400 mm, and a hot press at 8 °C for 2 hours to obtain a sintered body. The obtained sintered body was processed into a diameter of 152 mm and a thickness of 5 mm to obtain a Sn〇2-Sb203-based sputtering target. Evaluations 1, 2, 4, and 5 were carried out using the obtained sputtering target. As shown in Table 2, the Sn02-based sputtering target to which Sb203 was added was compared with the constituents of the present invention, and it was found that the film resistivity g without heat treatment was extremely high, and the film resistivity before and after the heat treatment was extremely high, and the bending strength was high. It is lower and there are many abnormal discharges. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a compositional surface scan image of molybdenum obtained in accordance with the sintered body of Example 4 of the present invention. Fig. 2 is a view showing a compositional surface scan image of molybdenum obtained by sintering of Example 19 according to a comparative example. The white block portion in the figure indicates molybdenum agglomeration. Ιιη 1.0 shows the big fruit of the gold and the -18- which is still in the body

Claims (1)

1378149 X. Application for patent scope Patent Application No. 97111191 Patent Revision of Chinese Patent Application 1. A Sn 〇 2 sputtering target characterized by containing 1 > 5 to 3% by mass of Ta205 ' and 0.25 to 2% by mass of Nb 205 and Sn 〇 2 as a remaining portion and inevitable impurities It is composed of a sintered body. The sputtering target according to claim 1, wherein the content of Nb205 is 0.25 to 1% by mass. The splash-spraying target according to the first aspect of the invention, wherein the content of Ta2〇5 is from 1 to 5 to 3.0% by mass, and the content of Nb2〇5 is from 0_25 to 0.75 mass% of Nb205. 4. The sputtering target according to claim 1, wherein the condensed phase formed by Ta having a Feret's diameter of 10 μm or more is substantially not contained. 5. The sputtering target according to the first aspect of the invention, which has a bending strength of 10 kgf/mm2 or more measured in accordance with JIS-R-1601. 6. The sputtering target according to the first aspect of the invention, wherein the number of abnormal discharges generated during the plating of the ff power density of 1 to 50 W·hr/cm 2 is 30 or less. 7. The sputtering target according to any one of claims 1 to 6, wherein the sputtering target is used for producing a sputtering film having a resistivity of less than 9 m Ω • cm. The sputtering target according to any one of claims 2 to 6, wherein a sputtering film having a resistivity of less than 6 m Ω · cm is used. 9. The sputtering target according to claim 7, wherein the resistivity is not achieved by heat treatment. 10. A Sn02 sputter film which is a sputter film produced by sputtering using a sputtering target according to any one of claims 1 to 9. It is characterized in that the film contains 1.5 to 3.5% by mass of Ta205, and 0.25 to 2% by mass of Nb205, and as the remaining part, Sn02 and unavoidable impurities. 11. The sputter film according to claim 10, wherein the content of Nb205 is 0.25 to 1% by mass. 12. The sputter film according to claim 10, wherein the content of Ta205 is 1.5 to 3.0% by mass, and the content of Nb205 is 0.25 to 0.75 mass% of Nb205. 13. The sputter film according to claim 10, which has a resistivity of less than 9 m Ω · cm. 14. The sputter film according to claim 10, which has a resistivity of less than 6 ηηΩ · cm. The sputter film according to claim 13, wherein the resistivity is not achieved by heat treatment. The sputter film according to any one of the items 1 to 5, wherein the resistivity of the sputter film after the heat treatment of the sputter film is heat-treated, The rate of change of the resistivity of the sputtered -2-1378149 coated film is less than 1%. -3-