TW201139706A - Pure copper plate production method, and pure copper plate - Google Patents

Abstract

Disclosed is a pure copper plate production method wherein post-hot-forging and post-hot-rolling cold forging and cold rolling, and subsequent heat processing are unnecessary. Further disclosed is a pure copper plate having a fine structure which is obtained according to the disclosed production method and which is provided with a high special grain boundary ratio due to the formation of a twin crystal structure by means of partial recrystalisation, and is particularly suitable for copper target members for sputtering, or anodes for plating, or similar. A pure copper ingot having a purity level of 99.96 weight% or higher is heated to 550-800 DEG C. A hot-rolling process is carried out wherein the total rolling rate is 85% or higher, the temperature at rolling completion is 500-700 DEG C, and which includes at least one finishing rolling pass having a rolling reduction rate for one pass of 5-24%. Then, rapid cooling from the rolling completion temperature to 200 DEG C or lower is carried out at a cooling speed of 200-1000 DEG C/min, as required.

Description

201139706 VI. Description of the Invention: [Technical Field] The present invention relates to a method for producing a pure copper plate having good quality, and in particular, relates to a double formed by partially recrystallizing together with a fine structure A method for producing a pure copper plate having a high specific grain boundary ratio, and a pure copper plate suitable for use in a copper target material for sputtering or an anode material for plating produced by the production method. The case is based on the purpose of the special request 2010-26455, which was filed on February 9, 2010, and the content is claimed here. [Prior Art] A pure copper plate is usually produced by subjecting a pure copper ingot to hot rolling or hot forging, applying cold rolling or cold forging, and then applying heat treatment for stress relief or recrystallization. Such a pure copper plate is used to be processed into a desired shape by sawing, cutting, embossing, cold forging, etc., in order to reduce cracking or deformation during processing, it is required to have a small crystal grain size and a crystal structure. The residual stress is small. Further, the pure copper plate produced by the above method has recently been used as a sputtering target for a wiring material of a semiconductor element. As a wiring material for a semiconductor element, A1 (a specific resistance of about 3.1 μΩ · cm) has been used. However, the copper wiring of a lower resistance (a specific resistance of about 1. 7 μΩ · cm) is put into practical use as the nearest wiring is miniaturized. As a forming process of the copper wiring, copper is electroplated by forming a diffusion barrier layer such as Ta/TaN in a recess of a contact hole or a wiring trench, and sputtering of pure copper is performed to form a base layer for performing the electric ore ( Kind-5- 201139706 sublayer). Usually, 4N (purity of 99.999% or more) to 6N (purity of 99.9999% or more) is produced by using 4N (purity of 99.99% or more: gas component exclusion) electrolytic copper as a crude metal 'by a wet or dry high purity process' The purity of the high-purity copper 'is made into a pure copper plate by the above method, and is processed into a desired shape, and then used as a sputtering target. In order to produce a low-resistance sputtering film, the content of impurities in the sputtering target is suppressed to below - and the additive element for alloying must be reduced to a certain level or less. In order to obtain uniformity of the thickness of the sputtering film, sputtering must be suppressed. The deviation of the crystal grain size and crystal orientation of the target. As a conventional method for industrially producing such a pure copper target for sputtering, Patent Document 1 discloses that an ingot of pure copper having a purity of 99,99 5 wt% or more is thermally processed, and then annealed at a temperature of 900 ° C or lower. Subsequently, the inter-cold rolling is performed at a rolling ratio of 40% or more, and then recrystallization annealing is performed at a temperature of 500 ° C or lower to obtain a substantially recrystallized structure, and the average crystal grain size is 80 μm or less, and the Vickers hardness is 100. The following method of sputtering a copper target. Further, Patent Document 2 discloses that a high-purity copper ingot of 5 N or more is subjected to hot working such as hot forging or hot-rolling, and the processing rate of cold rolling or cold forging is 3 0% or more of cold working, at 305 to 5 〇 (TC is subjected to heat treatment for 1 to 2 hours, and Na and K contents are each 0.1 ppm or less, and Fe, Ni, Cr, Al, Ca, and Mg contents are each Lppm or less, the carbon and oxygen contents are each 5 ppm or less, the u and Th contents are each 1 ppb or less, and the copper content after removing the gas component is 99.999% or more. Further, the average particle diameter of the sputtering surface is 250 μm or less, and the average particle diameter is deviation

-6- 201139706 Method for sputtering copper target with a X-ray diffraction intensity ratio of i (1 1 1 ) /1 ( 200 ) with a sputtering surface of 2.4 or more and a deviation of ±20 % or less . Further, Patent Document 3 discloses a surface layer of an ingot formed by removing high-purity copper and an additive element having a purity of 6 N or more, and is obtained by hot forging, hot rolling, cold rolling, and heat treatment, and contains 0.5 to 4.0. A wt% Al, Si is a copper alloy sputtering target of 0.5 wtppm or less, a copper alloy sputtering target containing 0.5 to 4.0 wt% of Sn, and a Μη of 0.5 wtppm or less, and a total amount of 1 in this case One or two or more copper alloy sputtering targets selected from Sb, Zr, Ti, Cr, Ag, Au, Cd, In, As below Owtppm. In particular, in the examples, it is described that after the surface layer of the cast sharp produced is removed to have a thickness of <t»160 mmx and a thickness of 60 mm, it is forged at 400 ° C to be φ 2 00 ηιηι, and then calendered at 40 (TC heat rolling). (j> 270mm X thickness: 20mm, and then cold rolling, rolling to φ360ιηπι thickness 10mm, heat treatment at 500 °C for 1 hour, the target is rapidly cooled to become a target material. Such a copper for sputtering In the conventional method for producing a pure copper plate, in order to obtain a homogeneous and stable recrystallized structure, a pure copper ingot is hot forged or heat-rolled, and then subjected to cold forging or cold rolling, and then cold rolling is performed. In the case of the heat treatment, the prior art is disclosed in Japanese Patent Application Laid-Open No. Hei No. Hei. No. Hei. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION In the conventional method of industrially manufacturing a large-sized pure copper plate having a homogeneous and stable crystal structure, hot forging is performed on a pure copper ingot or After hot rolling, it is necessary to apply cold forging or cold rolling and heat treatment, but the suppression of abnormal discharge due to high output sputtering of the sputtering target, the improvement of the homogeneous solubility of the plating anode, and the heat dissipation substrate The heat-resistant fatigue property is difficult to cope with only the micronization. The present invention has been made in view of such circumstances, and provides a heat treatment between hot forging or hot rolling without further application of cold forging or cold rolling and subsequent heat treatment. A method for producing a pure copper plate, and a copper plate having a high specific grain boundary ratio by partially recrystallizing together with the fine structure obtained by the production method, and is particularly suitable for copper for sputtering A pure copper plate such as a target material or an anode for plating. The means for solving the problem The present inventors conducted a dedicated review and found that it is not dependent on the conventional side, and it is forged or hot by ingot of pure copper. After the inter-calendering, a conventional method of performing cold forging or cold rolling and subsequent heat treatment to promote recrystallization to obtain fine and homogeneous crystal grains By the ingot of copper, in order to suppress the growth of crystal grains, under certain conditions of heat between the rolling part by recrystallization and promote the formation of twins tissue, and

-8- 201139706 In order to stop grain growth and to rapidly cool under certain conditions, a pure copper plate having a finer metal structure having a high specific grain boundary ratio can be produced. The method for producing a pure copper plate of the present invention is characterized by: The ingot of pure copper having a purity of 99.96 wt% or more is heated to 550 ° C to 80 (TC, the total rolling ratio is 85% or more, the temperature at the end of rolling is 500 to 700 t, and the rolling is performed once per pass (one pass The reduction ratio of 5 to 24% of the finishing heat is one-pass or more hot-rolling processing, and is characterized by: 200 ° C to l ° ° C / as needed The cooling rate of min is rapidly cooled from the temperature at the end of the rolling to a temperature of 200 ° C or lower. In order to obtain fine crystal grains, the formation of a twin crystal structure is promoted by partial recrystallization, and the grain boundary is improved. The ratio of the structure of the ratio is the temperature at which the finishing heat is rolled in the end step of the hot rolling (hereinafter referred to as the rolling end temperature), and the rolling reduction rate per one pass of the finishing heat rolling. Inter-calendering, when the calendering end temperature is not At 5 00 ° C, or when the reduction rate per pass is less than 5%, partial recrystallization is not sufficient, and when the calendering end temperature exceeds 70 (TC, or reduction rate per pass) When it is 25% or more, the dynamic recrystallization system in the calendering between the heat and the heat becomes a dominant factor, and it is difficult to obtain a high specific grain boundary ratio with the formation of the twin crystal structure due to partial recrystallization. The calendering end temperature is 500 to 7 〇〇 ° C, and the hot intercalation starting temperature can be 550 to 800 ° C. Further, the total calendering rate due to the intercalation calendering is preferably 85 % or more, due to the total rolling ratio. 85% or more can suppress the coarsening of the crystal grain size and reduce the variation of the particle diameter. If the total rolling rate is less than 85 %, the crystal grain size tends to be -9 - 201139706, and the grain The deviation of the diameter is increased. In addition, the formation ratio of the twin crystal structure is promoted by the rolling reduction ratio of the hot rolling between 5 and 24%, and the specific grain boundary ratio is increased. The organization improves the integration of the crystal grain boundaries, and the crystal structure becomes fine and uniform. Calendering between heat and heat, as long as it is in the range of 5 00 to 7 00 ° C, the reduction ratio per pass is 5 to 24%, and at least one pass of rolling can be performed, but it is also possible to continue the plurality of passes. In particular, the rolling process can be further promoted by repeating rolling in a plurality of passes. The pure copper plate thus produced is effective for use in a sputtering target, an anode for plating, a heat dissipation substrate, and the like. Further, after such heat-to-heat rolling is completed, it can be rapidly cooled to a temperature of 20 (TC or lower) at a cooling rate of 200 to 1 000 ° C / min. When the cooling rate is less than 200 ° C / min, there is a lack of suppression. The effect of growth of crystal grains, even if it exceeds 1 000 °C/min, does not contribute to the above-mentioned grain growth inhibition effect. A more preferable cooling rate is in the range of 300 to 600 ° C / min. When cooling is performed at a cooling rate of such a range up to 20 (temperatures below TC), the growth of crystal grains can be stopped, and fine crystal grains can be obtained. On the other hand, rapid cooling is stopped at a temperature exceeding 200 °C. Then, since the crystal grains are gradually grown due to the high temperature state, the pure copper plate produced by the production method of the present invention is characterized by: a special grain of a special grain boundary measured by the EBSD method. The ratio of the boundary length La to the total grain boundary length L (La/L) of the grain boundary is 55 % or more. Since the frequency of this special grain boundary is as high as 55% or more, the crystallization is improved.

S -10- 201139706 The integration of the grain boundary, various characteristics such as the sputtering characteristics of the sputtering target, the solubility of the plating anode, and the deformation characteristics of the plate material are improved. The pure copper plate of the present invention is suitable for use in a target for sputtering. In particular, since it is partially recrystallized to form a twin structure, and has a high specific grain boundary ratio, even in the sputtering at a high output, the occurrence of abnormal discharge can be suppressed. Advantageous Effects of Invention According to the present invention, it is possible to produce a pure copper plate having fine and uniform crystal grains, which is suitable for producing a copper target material for sputtering which is less likely to cause abnormal discharge even at a high output or plating which exhibits uniform solubility. Apply anode material, etc. [Embodiment] Mode for Carrying Out the Invention Hereinafter, an embodiment of the present invention will be described. The pure silver plate of this embodiment is copper-free copper having a purity of 99.96 wt% or more, or oxygen-free copper for an electron tube of 99.99 wt% or more. Further, the average crystal grain size obtained by the EBSD method is 1 〇 to 200 μmη, preferably 80 μηι, and the total grain boundary length of the special grain boundary determined by the EBSD method is La to the whole grain of the grain grain boundary. The ratio of the length L of the boundary (Lct/L) is 55% or more. Further, when large crystal grains having a particle diameter of more than 200 μm are mixed, fine cracking tends to occur on the surface during cutting. This squeezing system is as shown in Fig. -11 - 201139706. When cutting materials such as a milling cutter, the cutting marks W occurring in the cutting direction (the direction indicated by the arrow A) are in the cutting direction. In the orthogonal direction, the rib-like fine unevenness as shown by the symbol C occurs. If this cracking occurs, it will damage the appearance of the product. It is not realistic to make the average crystal grain size less than 1 Ομηι, resulting in an increase in the production cost. In addition, the ratio of the length of the special grain boundary is 55% or more, thereby improving the integration of the crystal grain boundary, and is effective for applications such as a sputtering target, an anode for plating, and a heat dissipation substrate. The result of observation of the cross section of the grain boundary of the crystal grain boundary is defined as the boundary between the crystals when the alignment between two adjacent crystals is 15 or more. The crystallographic system of the special grain boundary is defined by the CSL theory (1<:1'0115616131.:7^3118.1^61 Soc. ΑΙΜΕ, 185, 501 (1 949)) as having 3 $ 2929 The crystal grain boundary (corresponding to the grain boundary) is defined as the inherent orientation of the grain boundary. The lattice orientation defect Dq satisfies 〇9$15°/11/2 (0,0· Brandon: Acta. Metallurgica. Vol. 14, P1479, Crystal grain boundary of 1966). Among all the crystal grain boundaries, if the length ratio of the special grain boundary is high, the integration of the crystal grain boundaries is increased, and the sputtering target or the plating anode widely used as a pure copper plate can be extracted. Or characteristics of a heat sink substrate, etc. In other words, in the sputtering target, the abnormal discharge characteristics at the time of sputtering are related to the crystal structure, and the purity of the material is reduced, that is, the impurity content is reduced (JP-2002- 293 1 3), The homogeneity of the diameter (W003/046250), the control of the crystal orientation of the structure (Special Kaiping 1 0-330923), etc.

S -12- 201139706 The splash shovel feature shows the means to suppress abnormal discharge. However, in recent years, in order to improve productivity, it is required to further increase the sputtering rate, and the shovel voltage is directed toward a high voltage. When the sputtering voltage is increased, the abnormal discharge is more likely to occur during sputtering. Therefore, only the conventional tissue control method is insufficient, and the abnormal discharge suppressing effect is insufficient, and further tissue control is required. In addition, the anode material for plating made of pure copper is used for the through-hole plating of a printed wiring board, etc., but the unevenness of the current density distribution occurs when the anode is dissolved, causing local conduction failure, resulting in insoluble slag. (slime)' is associated with poor plating or reduced production efficiency. As a countermeasure, it is effective to improve the in-plane solubility homogeneity of the dissolution surface of the anode, and to take measures to refine the crystal grains. However, in general, the grain boundary system is more soluble than the inside of the grain, and even if the in-plane dissolution homogeneity of the anode is improved by miniaturization, the grain boundary cannot be selectively dissolved, and the effect of miniaturization is limited. Therefore, it is judged that the solubility of the grain boundary itself is suppressed, and the occurrence of the above-mentioned slag is effective. However, such a viewpoint has not been reviewed in the past. Further, in the heat-dissipating substrate, since expansion and contraction are repeated at the time of use, it is important to have uniform deformation characteristics and excellent fatigue characteristics. In recent years, in hybrid vehicles or solar cells that have been popularized with the trend of energy saving and low CO, straight-and-AC inverter circuits are indispensable, and in order to dissipate heat generated during conversion, pure copper or low is used. The alloy copper plate serves as a heat sink substrate. In such applications, the current has increased due to the increase in size of the system, and the thermal load applied to the heat-dissipating substrate tends to increase. The heat-dissipating substrate requires long-term thermal fatigue resistance because it is often repeatedly thermally expanded/contracted during use. Regarding the thermal fatigue resistance, the homogeneity of the structure is important. However, in the past, only the uniformity of the structure was improved, and it was difficult to improve the fatigue characteristics accompanying the above-described large current. These problems can be solved by making the ratio of the length of the special grain boundary of the crystal grain boundary to 55% or more. In other words, in the sputtering target, since the sputtering surface is uniformly sputtered uniformly, the step of the crystal grain boundary which is a cause of abnormal discharge is less likely to occur, and as a result, the number of abnormal discharges is reduced. Regarding the anode for plating, it is judged that the special grain boundary system has a property closer to the solubility characteristic in the grain than the general grain boundary, and by using a copper plate having a higher grain boundary ratio, the in-plane dissolution homogeneity at the time of anodic dissolution is remarkable. The improvement is to keep the dissolved surface smooth, so that the occurrence of insoluble slag can be suppressed, and the quality of the formed plating film is increased. Further, in the substrate material for heat dissipation use, uniform deformation characteristics are exhibited, and even if repeated thermal expansion/contraction occurs, metal fatigue is less likely to occur, and fatigue characteristics are improved. By setting the length ratio of the special grain boundary to 55 % or more, the sputtering characteristics of the sputtering target, the solubility of the anode material for plating, and other characteristics such as deformation characteristics of the copper plate are improved, and the sputtering is effective. Applications such as plating targets, anodes for plating, and heat dissipation substrates. Next, a method of manufacturing such a pure copper plate will be described. This manufacturing method is a simple process in which the ingot of pure copper is heat-calendered, and the hot-rolling pass is subjected to the refining pressure of the specified condition, and then rapidly cooled as needed. Specifically, the ingot of pure copper is heated to 550 ° C to 80 ° C, and the gap between the calender rolls is gradually reduced and rolled to a designated number while repeatedly reciprocating between the calender rolls. The thickness is up. This multiple calendering station

S • 14 - 201139706 The total rolling rate is more than 85%. 'The end of the hot rolling is the end of the calendering. The calendering end temperature is 500~700 °C. 'The above-mentioned finishing heat rolling is performed every 1 pass. The reduction ratio is 5 to 24%. The continuous processing is performed by one pass or multiple passes. Then, 'as needed', rapid cooling is performed at a cooling rate of 2 Torr to 1 000 T:/min, and the rolling end temperature is set to a temperature of 200 ° C or lower. The usual method for producing a pure copper plate is generally hot rolling = > cooling two cold rolling = > heat treatment process, and the inter-heat rolling is processed at a high temperature of 8 50 to 900 ° C. When the inter-heat rolling is performed at such a high temperature, the crystal grain size is coarsened, and even if it is rapidly cooled, the average crystal grain size cannot be made finer to 80 μm or less. In the production method of the present embodiment, the inter-heat rolling starting temperature is 50,000 to 800 ° C, and the end temperature is in a relatively low temperature state of 500 to 700 ° C. If the end temperature of the inter-heat rolling exceeds 700 ° C Then, the crystal grain size rapidly increases, and it is difficult to obtain fine crystal grains even after rapid cooling. Further, even if the heat-to-heat rolling end temperature is less than 500 °C, the effect of refining the crystal grain size is saturated, and even if the temperature is lowered to be lower than the above, it does not contribute to miniaturization. Therefore, the calendering end temperature is 500 to 700 °C. Moreover, since the end temperature of the inter-heat rolling is 500 to 70 (TC, the starting temperature of the inter-heat rolling is 5 50 to 800 ° C ° and the total calendering rate due to the thermal interval is preferably 8 5 When the total rolling ratio is 85% or more, the coarsening of the crystal grain size can be suppressed and the variation can be reduced. If the total rolling ratio is less than 85%, the crystal grains tend to become larger. At the same time, the deviation becomes larger. At this time, among the plurality of calenderings, -15-201139706 is about the final stage of calendering, and the calendering rate is preferably 5 to 24% per one pass. Performing one or more passes in a continuous rolling process. By reducing the rolling ratio per pass to 5 to 24% in the final stage of the hot rolling, the ratio of the twin structure can be increased. The ratio of the length of the special grain boundary of the crystal grain boundary is 55% or more. The reduction ratio per pass is the rate of decrease in the thickness of the base material after rolling relative to the thickness of the base material before passing through the calender roll. (or the rate of decrease in the gap between the calender rolls in this pass relative to the gap between the calender rolls in the previous pass), The rate of decrease of the thickness of the base material after the end of rolling is compared with the thickness of the base material before rolling, that is, the thickness of the base material after passing through the calender roll is to, and the thickness of the base material after passing through the calender roll For h, the reduction ratio γ (%) per pass can be defined as ((to-t, ) /t〇) xl 00 ( % ). Moreover, after such heat-to-heat rolling is finished, It is rapidly cooled by water cooling at a cooling rate of 200 to 1 000 ° C / min until it reaches a temperature of 200 ° C or lower, which suppresses coarsening of the particle diameter after hot rolling. The cooling rate is less than 200 ° C / In the case of min, there is no effect of suppressing the growth of crystal grains, and even if it exceeds 1000 ° C / min, it does not contribute to the above-mentioned miniaturization. If cooling is performed at a cooling rate of such a range up to a temperature of 200 ° C or lower, then When the growth of the crystal grains is stopped, fine crystal grains can be obtained. If the rapid cooling is stopped at a temperature exceeding 200 ° C, the crystal grains gradually grow after being placed in a high temperature state. Embodiments of the invention.

S -16 · 201139706 The material used for the rolling is an oxygen-free copper (purity of 99.99 wt% or more). The material size before calendering was 650 mm x width 900 mm x thickness 2 90 mm, and various conditions such as heat rolling and subsequent cooling were combined as shown in Table 1 to prepare a pure copper plate. Further, the temperature measurement was carried out by measuring the surface temperature of the rolled plate using a radiant thermometer. [Table 1] Inter-calender rolling cooling start temperature °C End temperature °C Total rolling rate % Separation speed sub-speed 〇C/min Arrival temperature °C Example 1 562 553 92 1596x3 pass 209 181 2 592 583 88 10! Χ1 680 193 3 616 590 92 20 20% χ 4 261 185 4 637 614 92 20 ϋχ 3 passes 472 170 5 667 634 92 10% χ 3 passes 940 175 6 703 654 92 24% χ 2 passes 236 199 7 707 664 88 15知三道次254 192 8 713 669 92 15?ίχ3 passes 254 187 9 720 676 92 20%χ2 passes 516 180 10 732 691 88 5«χ3 passes 264 192 11 591 534 90 18%χ5 passes No rapid cooling 12 663 621 94 20% χ 2 passes no rapid cooling 13 753 635 86 1054x3 pass no rapid cooling 14 588 503 88 2256x2 pass no rapid cooling 15 728 683 96 8 ίίχ 2 passes without rapid cooling 16 662 621 92 16 %χ4 passes no rapid cooling 17 575 538 92 mxi pass no rapid cooling 18 559 521 92 15%x3 pass no rapid cooling comparison example 1 510 490 2 620 600 83 1514x2 pass 528 210 3 720 661 92 1554x1 pass 126 220 4 720 689 83 3054x1 pass 690 180 5 820 732 83 25 rounds 2 passes 281 180 6 848 760 92 20%x3 passes 146 180 7 920 818 83 305U3 pass 255 220 In Table 1, Comparative Example 1 has a rolling start temperature of 5 1 0 ° C (end expected temperature 490 ° C) The rolling is started, but since the temperature is too low, it becomes an overload state, and the calendering is continued. Therefore, for the pure copper plate other than Comparative Example 1, the average crystal -17-I:; 201139706 particle size, the specific grain boundary length ratio, the cracking state at the time of cutting, and the number of abnormal discharges when used as a sputtering target were measured. The amount of slag generated when plating an anode <average crystal grain size, special grain boundary length ratio> For each sample 'using water honing paper and diamond abrasive grains, after mechanical honing, a colloidal vermiculite solution is used. , finishing the honing. Then, the EBSD measuring device (S4300-SE manufactured by HITACHI Co., Ltd., OIM Data Collection manufactured by EDAX/TSL Co., Ltd.) and the analytical software (OIM Data Analysis ver. 5.2 manufactured by EDAX/TSL Co., Ltd.) were used to identify crystal grain boundaries and special grain boundaries. The length was calculated, and the average crystal grain size and the specific grain boundary length ratio were analyzed. First, using a scanning electron microscope, each measurement point (pixel) in the measurement range of the surface of the sample is irradiated with an electron beam, and the orientation of the adjacent measurement points is determined by the azimuth analysis of the backscattered electron beam diffraction. The measurement point between the difference of 15 or more is regarded as a crystal grain boundary. In the measurement of the average crystal grain size (the twin crystal is also used as the crystal grain count), the number of crystal particles in the observation range is calculated from the obtained crystal grain boundaries, and the crystal particle area is calculated by dividing the number of crystal particles in the range area, and the conversion is performed. It is a circle and becomes an average crystal grain size (diameter). Further, 'the total grain boundary length L of the crystal grain boundary in the measurement range is determined, and the position of the crystal grain boundary of the special grain boundary is determined by the interface of the adjacent crystal grain', and the full special grain boundary length La of the special grain boundary is obtained. The grain boundary length ratio Lcy/L of the total grain boundary length L of the above-mentioned measured grain boundary is regarded as the special -18-201139706 grain boundary length ratio. <Squeezing state> Each sample is made to be 100 00 200 mm The flat plate is made of a super-hard cutting tip of a milling machine, and is cut at a depth of 0.1 mm and a cutting speed of 5000 m/min. In the 500 μm square of the cutting surface, the length of 100 μm or more is investigated. There are several existences of cracks. <Number of sputter abnormal discharges> An integrated target including a backing plate portion was prepared from each sample so that the target portion had a diameter of 152 mm and a thickness of 6 mm, and the target was attached to a sputtering apparatus to allow the chamber to reach a vacuum pressure. Became lxl (below T5Pa, use Ar as the sputtering gas, the sputtering gas pressure is 〇.3Pa, and perform the sputtering test with a direct current (DC) power supply at a sputtering output of 2kW. The sputtering system is continuous for 2 hours. The arc counter attached to the power source counts the number of abnormal discharges due to abnormal sputtering. <Anode slag generation amount> A disk-shaped copper plate cut into a diameter of 270 mm is fixed to the electrode holder (the electrode area is approximately 53 0cm2 ) As an anode electrode, a 200mm diameter silicon wafer was used as a cathode, and copper plating was performed under the following conditions to measure the insoluble viscosity generated from the start of plating to the processing of the fifth wafer. The amount of slag is generated. In addition, the viscous slag is recovered and the weight is measured after drying. -19- 201139706 Plating solution: 70 g/l of copper pyrophosphate and 300 g/l pyrophosphoric acid are added to the ion exchange water. Potassium, use The ammonia water was adjusted to ρΗ8·5, plating conditions: stirring was carried out at a liquid temperature of 50 ° C by air stirring and cathode shaking, cathode current density: 3 A/dm 2 , plating time: 1 hour / piece. The results are shown. [Table 2] Average crystal grain size fi m Special bribe length ratio % Evaluation Surface 璁 璁 个 异常 异常 异常 异常 异常 异常 异常 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 实施 58 58 58 58 58 58 58 58 2 2 5 3 60 65 2 2 6 4 55 60 2 3 5 5 60 73 1 2 7 6 56 58 1 3 5 7 71 74 0 1 4 8 70 70 0 1 4 9 66 68 0 2 4 10 73 56 0 2 6 11 102 60 2 3 3 12 123 56 2 2 5 13 145 72 2 5 6 14 85 58 1 3 4 15 196 73 3 4 5 16 166 71 3 3 5 17 9β1 60 2 6 6 18 92 68 2 4 3 Compare Example 1 1111 - 2 95 45 5 21 16 3 136 43 4 34 15 4 90 47 5 16 20 5 88 50 5 13 12 6 157 53 5 11 13. 7 168 48 6 18 18 It is known that the pure copper plate produced by the production method of the present embodiment has an average crystal grain size of 10 to 200 Mm. In particular, in Examples 1 to 10 in which rapid cooling is performed after the coining, it is 10 to 80 μm, and the examples are -20-

S 201139706 Special grain boundary length ratio is more than 5 5 %. On the other hand, the pure copper plate of the comparative example had a specific grain boundary length ratio of less than 55%. From the results, it is understood that in the examples, the reduction in the hot pressing pressure is 5 to 24%, and in the evaluation of the sputtering target characteristics, the number of abnormal discharges during sputtering is small, and the anode for plating is used. In the evaluation of the dissolution characteristics, the amount of insoluble slag generated was small. The embodiments of the present invention are described above, but the present invention is not limited to the scope of the invention, and may be modified as appropriate without departing from the scope of the invention. For example, in the schedule of the hot press rolling, in the case of a plurality of passes, although the reduction ratio is fixed, it is not restricted by this, as long as each pass is 5~ With a reduction rate of 24%, the reduction rate per calendering pass can also be different. Further, in terms of obtaining a high specific grain boundary ratio, although it is not necessary to perform rapid cooling after the completion of the coining pass, it is effective in improving the homogeneity of the inside of the ingot and the surface, and therefore it is preferable to implement Fast cooling. In addition, the present invention is a product obtained by rapidly rolling to a temperature of 200 ° C or lower after being subjected to hot rolling under specified conditions, and thereafter is not subjected to cold rolling to obtain a pure copper plate, but may be a final finish after rapid cooling. A slight (calendering rate of several % or less) rolling is performed in the cold room. INDUSTRIAL APPLICABILITY The pure copper plate of the present invention can be applied to a sputtering target, a plating anode, or a target backing plate. Alternatively, it can be applied to a mold, a discharge electrode, a heat dissipation plate, and a heat sink - 201139706 , models, water-cooled plates, electrodes, electrical terminals, bus bars, gaskets, flanges, printing plates, etc. [Simple description of the drawing] Fig. 1 is a photomicrograph of the crack generated when the surface of the pure copper plate is cut. [Main component symbol description] w : Cutting marks c: Crushing 瑕疵 -22-

Claims (1)

201139706 VII. Application for Patent Fanyuan·1. A method for manufacturing a pure copper plate, characterized in that a pure copper ingot having a purity of 99.96 wt% or more is heated to 550 ° C to 800 ° C. The total rolling rate is 85. % or more, the temperature at the end of rolling is 500 to 70 0 ° C ' and the reduction ratio of one to one pass per pass is 5 to 24%, and the pass pressure is one pass or more. Hot intercalation processing. 2. A method for producing a pure copper plate, characterized in that a pure copper ingot having a purity of 99.96 wt% or more is heated to 550 ° C to 800 ° C. The total rolling rate is 85% or more, and the temperature at the end of rolling is 500. ~7〇〇°C' and the reduction ratio of 5~24% of the rolling pressure applied per pass is 1 or more times of hot pressing, and 200°C to 1 〇〇〇° The cooling rate of C/min is rapidly cooled from the temperature at the end of the rolling to a temperature of 200 ° C or lower. 3. A pure copper plate, which is a pure copper plate manufactured by the manufacturing method of the first application of the patent application, characterized in that: a special grain boundary length La of a special grain boundary determined by the EBSD method The ratio (La/L) of the total grain boundary length L of the boundary is 55% or more. 4. A pure copper plate, which is a pure copper plate manufactured by the manufacturing method of the second application of the patent application, characterized in that the total grain boundary length La of the special grain boundary determined by the EBSD method is a crystal grain boundary. The ratio of the total grain boundary length L (La/L) is 55% or more. 5. For the pure copper plate of the third application of the patent scope, it is a target for sputtering. 6. For a pure copper plate as claimed in item 4 of the patent scope, it is a target for splashing. 7. A pure copper plate according to item 3 of the patent application, which is an anode for plating -23-201139706. 8. A pure copper plate according to item 4 of the patent application, which is an anode for plating -twenty four-