TW200303931A - Sputtering target and method for producing the same - Google Patents

Abstract

A sputtering target is characterized in that the sputtering target will not form cracking, be damaged or generate abnormal discharge during sputtering, and can perform stable sputtering at a high speed, and can obtain a phase change photo recording medium with excellent recording regeneration characteristics under high productivity. The sputtering target is formed of a sintered body sintered from more than one oxide and more than one carbide. Furthermore, the sintered body contains 0.1wt% ~ 20 wt% of carbon content, and has a relative density of more than 70%. Particularly, the sintered body is formed of Mo oxide and silicon carbide, and contains 0.1wt% ~ 20 wt% of silicon carbide, and has a relative density of more than 70%.

Description

(1) (1) 200303931 (1) Description of the invention [Technical field to which the invention belongs] The present invention relates to a sputtering target used for manufacturing a rewritable optical information recording medium and a manufacturing method thereof, and the optical information recording medium is made by Laser beams and other phase-change optical recording media that cause a phase change in the recording layer to perform information recording, reproduction, and erasure. [Prior art] A phase-change optical recording disk is a type of rewritable optical recording disk that records information by reversible phase change of the recording layer (mostly between crystalline and amorphous). With a single magnetic head and a single-layer recording film, light modulation and rewriting can be performed. In addition, since the reflectance change signal accompanying the phase change is read, it has a compact read-only memory (CD-ROM, compact dist read only) Memory) and other existing optical recording disks are highly interchangeable. As a rewritable optical recording disk, it has been actively researched and developed in recent years and applied to rewritable digital versatile discs (DVDs). 〇Phase change optical recording media, such as phase change optical recording media, are usually recorded on the crystalline phase (erased state) of the recording layer by forming a recording mark with an amorphous phase with a laser beam. By detecting the crystalline phase and The reflectance of the amorphous phase is poor to obtain a reproduced signal. In addition, a single-beam, single-layer recording film can be obtained by changing the intensity between the amorphization intensity (peak power) and the crystallization intensity (bias power) when the signal is recorded. The combination can be optically converted and rewritten (direct rewrite, DOW, direct -6- (2) (2) 200303931 overwrite), a large-capacity and high-transfer-rate recording disk. On the other hand, increasing the capacity of the optical recording medium following the phase change requires that recording and reproduction be performed at a higher transfer rate, such as rewriting at a so-called high line speed of 10 m / sec. In the past, phase-change optical recording media had a problem of low erasing rate at such a high line speed. In order to solve this problem, many protection layers formed by connecting to the recording layer have been reviewed. In addition, multiple layers of protection have been proposed for sharing protection. The recording layer and the function of promoting the crystallization of the recording layer are provided with a thin interface layer formed between the recording layer and the protective layer and connected to the recording layer. In addition, the material constituting the protective layer or the interface layer of such a phase-change optical recording medium mainly uses an oxide, and the forming method of the protective layer or the interface layer is mostly using a sintered body composed of these materials as a spray. Splatter method of splash target. [Summary of the Invention] [Problems to be Solved by the Invention] In the manufacture of phase-change optical recording media, when a protective layer or an interface layer is formed, a thin film obtained by sputtering using only an oxide target has insufficient adhesion and has the obtained phase. The recording sensitivity characteristics of the variable optical recording medium are poor. In order to solve these problems, if a material with an additive added to the oxide is used as a material constituting a protective layer or an interface layer, when a sputtering target with an additive added to the oxide is sprayed, cracks or breakages are likely to occur, making it impossible to The problem of increasing productivity. In addition, there is a problem in that the yield of the product is lowered due to particles generated by the abnormal discharge during sputtering. -7- (3) (3) 200303931 The present invention provides a sputtering target useful for forming a protective layer or an interface layer of a phase-change optical recording medium in view of the above circumstances, and is characterized in that the sputtering target can be fast and stable A sputtering method that can obtain a phase change optical recording medium with excellent recording and reproduction characteristics with high productivity, and also provides a method for manufacturing such a sputtering target that can be easily and with good yield. [Embodiment] [Method of Solving the Problem] The inventor conducted an intensive review in order to solve the above problems, and found that by using a raw material powder of oxide and carbide, the obtained mixed powder was sintered under specific conditions. The sputtering target does not generate cracks or breakage during sputtering, and can perform sputtering quickly and stably, thereby obtaining a phase change optical recording medium having excellent recording and reproduction characteristics. The present invention has been achieved based on the above research results. That is, the sputtering target of the present invention is composed of a sintered body composed of one or more substances selected from oxides and one or more substances selected from carbides, and is suitable as a protective layer for forming a phase-change optical recording medium. Or interface layer users. The carbide content in the sintered body is preferably 0.1 Wt% or more and 20 wt% or less, and the relative density is preferably 70% or more. The oxides constituting the sintered body are preferably one or more oxides selected from the group consisting of giant, silicon, aluminum, zinc, sharp, hafnium, zinc, indium, and tin. The carbides constituting the sintered body are more than one selected from silicon, Carbides of tantalum, titanium, niobium and tungsten are preferred. When two or more kinds of carbides are contained, the total amount of the carbides contained is preferably from 0.1% by weight to 20% by weight. -8- (4) (4) 200303931 The carbides constituting the sintered body are particularly the carbides of silicon. When the carbide is a carbide of silicon, it is more preferable that the carbide is substantially free of elements other than Si. In addition, the sputtering target of the present invention is a sintered body containing a group of oxides and silicon carbides, which is characterized in that the silicon carbide content in the sintered body is 0.1 wt% or more and 20 wt% or less, and the relative density is 70%. The above. In this case, it is preferable that the sintered body is substantially free of carbides of elements other than Si. In the present invention, a carbide substantially containing no element other than Si means that the diffraction peak of the carbide belonging to the element other than Si in the X-ray diffraction pattern cannot be confirmed clearly. More specifically, it means, for example, the ratio of the intensity I max of the maximum diffraction peak in the X-ray diffraction pattern of the sintered body to the intensity I c of the diffraction peak of carbides of elements other than Si (I c / I max) is less than 0.01. The oxides and silicon carbides in the present invention can be Ta205 and SiC, respectively. The method for manufacturing a sputtering target according to the present invention includes a step of sintering a mixed powder obtained by mixing an oxide and a raw material powder of a carbide to obtain a sintered body. In the method for manufacturing a sputtering target composed of a sintered body composed of a carbide substance, the aforementioned mixed powder is characterized in that an average particle diameter of 15 μm or less is used, and the content of the carbide powder in the aforementioned mixed powder is 0.1. Above wt% and below 20wt%, and under the sintering temperature of 900 ° C and above, the holding time at the sintering temperature is more than 30 minutes, and the temperature reduction rate after the sintering is 30 (TC / hr (5) (5) 200303931 or less) In addition, the method for manufacturing a sputtering target of the present invention includes a step of sintering a mixed powder obtained by mixing a raw material powder of giant oxide and silicon carbide to obtain a sintered body. The method for manufacturing a sputtering target composed of a sintered body composed of silicon carbide is characterized in that the aforementioned mixed powder uses an average particle size of 15 μm or less, and the aforementioned mixing The content of silicon carbide powder in the end is 0.1% by weight to 20% by weight, and the sintering temperature is above 90 0 ° C, the holding time at the sintering temperature is more than 30 minutes, and the cooling rate after the sintering is 3 00 ° Sintering under conditions below C / hr *. Particularly, it is preferable that the sintering temperature is 900 ° C to 1200 ° C, so that a spatter composed of a sintered body composed of a group oxide substantially free of TaC and the like can be obtained. The target is preferably sintered at a sintering pressure of 100 kg / cm2 or more by using a hot pressing method, so that a higher density sintered body can be easily obtained. The present invention will be described in more detail below. The sputtering target of the present invention is characterized by its characteristics The sputtering target is composed of a sintered body composed of one or more substances selected from oxides and one or more substances selected from carbides, and the carbide content in the sintered body is 0.1 wt% or more and 20 wt% or less. And the relative density is 70% or more. Moreover, the sputtering target of the present invention is a sintered body containing a group of oxides and silicon carbides, and the silicon carbide content in the sintered body is 0.1 wt% or more 20 wt% or less, and relative density above 70% If the content of carbides such as SiC in the sintered body exceeds 20wt%, the transparency of the film obtained by sputtering is reduced, and it is impractical due to the low recording and reproduction characteristics. Also, if it is less than 0.1 wt%, there is no effect of improving the recording sensitivity. The carbon (6) (6) 200303931 in the sintered body is more preferably 0.1 to 15% by weight, and more preferably 0.1 to 10% by weight. In addition, by making the relative density of the sintered body more than 70%, the The occurrence of cracks or breakages and the occurrence of abnormal discharges are sharply reduced. The relative density of the sintered body is more preferably 80% or more, and more preferably 90% or more. The oxide constituting the sintered body can be used, for example, one or more selected from giant, As for the oxides of silicon, aluminum, titanium, niobium, chromium, zinc, indium, and tin, in terms of improving the erasing rate characteristics of the phase change optical recording medium made using the obtained sputtering target, one or more members are selected from the group consisting of silicon, silicon, Oxides of aluminum, titanium and niobium are preferred. However, since the refractive index of SiO2 is low, a phase change optical recording medium made of a sputtering target composed of a sintered body containing SiO2 as a main component may have a relatively low signal intensity. In addition, for the carbides constituting the sintered body, in order to improve the recording characteristics of a phase-change optical recording medium produced using the obtained sputtering target, one or more types of carbons selected from silicon, giant, titanium, niobium, and tungsten are used. Good thing. In particular, in terms of recording sensitivity improvement, silicon carbide is most effective. Therefore, when the carbide is a silicon carbide, it is preferable that the carbide is substantially free of elements other than Si. In terms of simultaneously improving the erasing rate characteristics and recording sensitivity characteristics of a phase change optical recording medium, it is preferable to use a sputtering target composed of a sintered body containing a giant oxide and a silicon carbide. In this case, it is also preferable that the carbide is substantially free of elements other than Si. When using a sputtering target composed of a sintered body containing the produced TaC by-product, when compared with a sputtering target composed of a sintered body containing no TaC by-product, the elimination rate of the phase change optical recording medium obtained by the former Degraded characteristics. On the other hand, the oxide constituting the above -11-(7) (7) 200303931 sintered body may use only a giant oxide, or an oxide containing tantalum, such as an oxide of indium or an oxide of thorium, This can further improve the recording sensitivity characteristics. In addition, molybdenum oxide, indium oxide, chromium oxide, and silicon carbide can be used, for example, Ta205, Ιη203, ZrO2, and SiC. As described above, the sputtering target system of the present invention is suitable as a forming phase. Users who change the protective layer or form the interface layer of the optical recording medium. The following is a description of a phase change optical recording medium suitable for use with the sputtering target of the present invention. This type of phase-change optical recording medium is a multi-layer film including a protective layer and a recording layer formed on a substrate, and information is recorded and eliminated using a reversible phase change between a crystalline phase and an amorphous phase of the recording layer. At least, the recording layer that can protect the reversible phase change between the crystalline phase and the amorphous phase is not affected by the heat generated during the recording and reproduction of the substrate. The recording layer is protected physically and chemically. A protective layer made of a dielectric. The protective layer is mostly formed on both sides of the recording layer, and may be formed only between the substrate and the recording layer, or may be formed only on the side opposite to the substrate of the recording layer. The protective layer can be directly connected to the recording layer, but in order to exert functions such as preventing atom diffusion into the recording layer or promoting crystallization of the recording layer, a thin interface layer may be formed by connecting the recording layer and the protective layer to the recording layer. In this case, the protective layer may be directly laminated on the interface layer, or may be laminated through any other layer. The interface layer may be formed on both sides of the recording layer, or may be formed on only one side of the substrate or on the opposite side of the substrate. In addition, an interface layer formed by using the sputtering target of the present invention can be formed on either side of the recording layer, and on the other hand, a boundary formed by using other materials can also be formed. -12- (8) (8) 200303931 Surface layer. In addition, as described above, the interface layer is formed by being connected to the recording layer on both sides of the recording layer or on the opposite side of the substrate, and can play a function of preventing atoms from diffusing into the recording layer or promoting crystallization of the recording layer. Its thickness is 0.1. To 20 nm, more preferably 0.2 to 10 nm, and most preferably 0.2 to 2.5 nm. As a substrate for such a phase-change optical recording medium, there is no particular limitation as long as it is sufficiently transparent to the laser wavelength range used, and can meet the characteristics of a media substrate, such as mechanical properties. Glass, polycondensation, etc. can be used. Carbonate, amorphous polyolefin, etc. In addition, if the laser light for recording and reproduction does not pass through the substrate and is reflected from the recording layer side, the substrate need not be transparent and can satisfy mechanical characteristics such as the characteristics of a media substrate. The protective layer is formed of a film that is transparent to the laser wavelength range used. In addition to the film formed by using the sputtering target of the present invention, films such as SiN, AIN, SiAlON, ZnS-Si02 can also be used. The recording layer is composed of a film having a reversible phase change, such as a GeSbTe-based thin film and an InSbTe-based thin film. In addition, the phase-change optical recording medium generally forms a reflective layer that reflects the irradiated laser light and returns to the signal detection system. The reflective layer is made of aluminum alloy or silver alloy with high reflectivity to the laser wavelength range used. Made of film. In addition, the above protective layer not only plays a role of protecting the recording layer, but also improves the light absorption efficiency of the recording layer. Since it also has the task of increasing the amount of reflected light change before and after recording, its thickness must consider the laser wavelength, The film thickness of the recording layer is optimally designed. In addition, after forming these layers, a protective coating layer composed of synthetic resin or the like may be formed thereon as needed. The following is an example of a more detailed manufacturing method of the sputtering target of the present invention. According to the composition specified in -13- (9) (9) 200303931, the raw material powder of oxide and carbide is compounded, and dry or wet uniform mixing is performed by, for example, a ball mill to obtain a mixed powder. The content of the carbide powder in the mixed powder obtained at this time is preferably from 0.1 to 20% by weight, more preferably from 0.1 to 15% by weight, and even more preferably from 0.1 to 10% by weight. If the content of the carbide powder exceeds 20 wt%, the transparency of the film obtained by sputtering with the obtained sputtering target is reduced, which is impractical due to the low recording and reproduction characteristics. If it is less than 0.1 wt%, the effect of improving the recording sensitivity is not obtained. As the raw material powder for making the sintered body for the sputtering target of the present invention, the oxide powder and carbide powder used are not particularly limited, and commercially available powders can be used. In order to obtain a more uniform high-density sintered body, the obtained mixed powder is used. The average particle diameter is preferably 15 μm or less, more preferably the average particle diameter is 10 μm or less, and most preferably the average particle diameter is 5 μm or less. The obtained mixed powder is temporarily formed by a hot press or the like, and sintered in an atmospheric pressure sintering furnace. In order to further increase the sintering density, it is preferable to charge the obtained mixed powder in a graphite mold or the like and press sinter with a hot press. Moreover, a sintered body can also be formed by HIP. During sintering, if the cooling rate is higher than 3 00 ° C / hr, the sintered body may have defects such as cracks or breakage. Therefore, the cooling rate is set to 3 00 ° C / hr or less. The cooling rate is more preferably 200 ° C / hr or less, and most preferably 100 ° C / hr or less. The sintering temperature is more than 900 t, more preferably 1 000 ° C, and most preferably 1 100 ° C. If it is lower than 900 ° C, it is difficult to obtain a sintered body having a high sintered density of 70% or more. Even if the hot pressing method is used, a very high pressure is required. When manufacturing sintered bodies containing giant oxides and silicon carbides, -14- (10) 200303931 is preferred so that TaC is not generated in the sintered body, and the sintering temperature is preferably 900 ° C to 1 200 ° C. In order to increase the sintering density, the sintering pressure when using the hot pressing method is preferably 100 kg / cm2 or more, more preferably 150 kg / cm2 or more, and most preferably 200 kg / cm2 or more. The retention time at the sintering temperature is preferably 30 minutes or more, more preferably 1 hour or more, and most preferably 2 hours or more. The sintered body obtained as described above is processed into a predetermined shape by dry or wet machining, and may be connected to a base plate for efficiently cooling the hot sprayed heat, if necessary, to produce the sputtering target of the present invention. The shape of the spray target can be appropriately selected according to the spray device used, for example, it is generally a round shape with a diameter of about 3 to 8 inches, or (4 to 6 inches) X (5 to 20 inches). Type and so on. The thickness of the sputtering target is generally about 3 to 20 mm.

[Examples] The present invention will be described in detail below based on examples, but the present invention is not limited to these. (Example 1) Ta205 powder and Sic powder were used as raw material powder. SiC powder was added to the end of Ta205 · to make the SiC content 2.5% by weight. The SiC powder and zirconia beads were simultaneously poured into a resin vessel and mixed with a ball mill for 2 hours. The obtained mixed powder having an average particle diameter of 1 / zm was charged into a hot-pressed graphite • 15- (11) (11) 200303931 model in a pure argon gas stream at a sintering temperature of 1 100 ° C and a sintering pressure of 200 kg. / cm2 under conditions of hot press sintering to produce a sintered body. The heating rate was 200 ° C / hr, the cooling rate was 100 ° C / hr, and the holding time was 2 hours. The temperature mode and pressure mode of the hot pressing are shown in FIG. 1. The obtained sintered body was processed into a raw plate shape (101.6 mm in diameter and 6 mm in thickness) by machining. Create a sputtering target connected to a copper base plate. A protective layer was formed using the above-mentioned sputtering target, and a phase change optical recording medium having a structure as shown in Fig. 2 (a) was manufactured. It was formed on a dish-shaped substrate 311 made of polycarbonate with a 0.7 μm width groove formed by a 1.4 μm pitch using the above-mentioned sputtering target in an argon gas (0.45Pa) containing 5% by volume oxygen. The film of the first protective layer 312 (film thickness: 100 μm). Then, a Ge2Sb2Te5 alloy target was subjected to DC sputtering under a pressure of 0.45 Pa of argon gas to form a film (film thickness: 20 nm) of the recording layer 3 13. In addition, using the above-mentioned sputtering target, RF sputtering was performed in an argon gas (0.45Pa) added with 5% by volume of oxygen to form a film of the second protective layer 314 (film thickness · 20 nm). Thereafter, a reflective layer 315 (film thickness: 1001101) was formed using an Al-3wt% Cr alloy target. A protective coating layer 316 having a thickness of 10 μm of an ultraviolet curing resin is formed thereon to produce a phase-change optical recording medium (a phase-change optical recording medium having such a structure hereinafter is also referred to as “phase-change optical recording medium I” or “media I "). An interface layer was formed using the above-mentioned sputtering target, and a phase change optical recording medium having a structure not shown in Fig. 2 (b) was manufactured. RF sputtering (argon gas (0.45Pa)) was performed on a dish-shaped substrate 321 made of polycarbonate with a groove width of 0.411 μm formed at a pitch of 1.4 μm, using a sputtering target composed of 2113-2 0 mol% Si02. ) To form a first protective layer 3 22 with a film thickness of 100 nm. On this, -16- (12) (12) 200303931 was subjected to RF sputtering in an argon gas (0.4 5 Pa) added with 5% by volume of oxygen using the above-mentioned sputtering target to form a film of the first interface layer 323 (film Thick: 2nm). Then, a Ge2Sb2Te5 alloy target was subjected to DC sputtering under an argon pressure of 0.45 Pa to form a film of a recording layer 324 (film thickness: 20 nm). Further, using the above-mentioned sputtering target, RF sputtering was performed in an argon gas (0.45 Pa) to which 5% by volume of oxygen was added to form a film (film thickness: 2 nm) of the second interface layer 325. Thereafter, RF sputtering (argon gas (0.45 Pa)) was performed using a sputtering target composed of ZnS-20 mol% SiO 2 to form a second protective layer 326 having a thickness of 20 nm. Thereafter, a reflective layer 327 (film thickness: 100 nm) was formed using an Al-3wt% Cr alloy rake. A protective coating layer 3 28 having a thickness of 10 μm of an ultraviolet curable resin is formed thereon to produce a phase-change optical recording medium (hereinafter, the phase-change optical recording medium having such a structure is referred to as “phase-change optical recording medium II” or “media II "). (Example 2)

A sputtering target was produced in the same manner as in Example 1 except that an oxide of aluminum, chromium, silicon, titanium, niobium, zinc, indium, or tin was used instead of Ta205 (Examples 2-1 to 8). Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium II (Example 3) were produced in the same manner as in Example 1 except that giant, titanium, niobium, tungsten, hafnium, bell, A sputtering target was produced in the same manner as in Example 1 except that carbide of aluminum or manganese was used instead of SiC (Implementation-17- (13) (13) 200303931 Examples 3-1 to 8). In addition, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium Π ° C were produced in the same manner as in Example 1. Example 4) Except that the content of SiC in the mixed powder was 0.1% by weight A sputtering target (Examples 4-1 to 6) was produced in the same manner as in Example 1 except that the amount was changed to 20 wt%. Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium Π were produced in the same manner as in Example 1. (Example 5) A sputtering target was produced in the same manner as in Example 1 except that the average particle diameter of the mixed powder was changed (Examples 5-1 to 3). (Example 6) A sputtering target was produced in the same manner as in Example 1 except that the temperature reduction rate was changed to 200 ° C / hr or 300 ° C / hr (Examples 6-1, 2). (Example 7) A sputtering target was produced in the same manner as in Example 1 except that the sintering temperature was changed to 900 ° C, 1 200 ° C, and 1 300 ° C (Examples 7-1, 3). Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium II were produced in the same manner as in Example 1. (Example 8) -18- (14) (14) 200303931 Except for normal pressure sintering with a sintering temperature of 90 ° C, 1100 ° C, 1200 ° C or 1300 ° C A sputtering target was produced in the same manner as in Example 1 except that sintering was performed (Examples 8-1, 4). Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium II were produced in the same manner as in Example 1. (Example 9) A sputtering target was produced in the same manner as in Example 1 except that the sintering pressure was changed to 100 kg / Cm2 or 150 kg / cm2 (Examples 9-1, 2). (Example 10) A sputtering target was produced in the same manner as in Example 1 except that the holding time of the sintering temperature was changed to 30 minutes or 1 hour (Examples 10 to 1, 2). (Example 1 1 ) Use Ta205 powder, SiC powder and ΙΟΟ203 powder as raw material powder, add SiC powder and In203 powder to Ta205 powder, so that the content of the latter two becomes 2.5 wt% of the total amount respectively, and combine it with chromium oxide beads Pour into a resin vessel and mix with a ball mill for 12 hours. Using the obtained mixed powder having an average particle diameter of 1 µm, a phase-change optical recording medium I and a phase-change optical recording medium II were produced in the same manner as in Example 1. (Example 1 2) -19- (15) (15) 200303931 A sputtering target was produced in the same manner as in Example 11 except that Zr02 powder (2.5 wt%) was used instead of 1η203 powder. Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium Π were produced in the same manner as in Example 1. (Comparative Example 1) A sputtering target was produced in the same manner as in Example 1 except that CeN powder or ZrN powder was used in place of the SiC powder (Comparative Examples 1-1, 2). Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium II were produced in the same manner as in Example 1. (Comparative Example 2) A sputtering target was produced in the same manner as in Example 1 except that the content of the SiC powder in the mixed powder was changed to 0% by weight or 2.5% by weight (Comparative Examples 2-1, 2). Further, using the obtained sputtering target, a phase-change optical recording medium I and a phase-change optical recording medium II were produced in the same manner as in Example 1. (Comparative Example 3) A sputtering target was produced in the same manner as in Example 1 except that a mixed powder having an average particle diameter of 20 μm or 18 μm was used (Comparative Examples 3-1, 2). (Comparative Example 4) A sputtering target was produced in the same manner as in Example 1 except that the temperature reduction rate was changed to 400 t / hr. -20- (16) (16) 200303931 (Comparative Example 5) A sputtering target was produced in the same manner as in Example 1 except that the sintering temperature was changed to 800 ° C. (Comparative Example 6) A sputtering target was produced in the same manner as in Example 1 except that the holding time of the sintering temperature was changed to 15 minutes. Observe the damage and cracks in the sintered bodies produced in the above Examples 1 to 12 and Comparative Examples 1-6, and perform density measurement and X-ray diffraction measurement on the obtained sintered bodies. In addition, the obtained sputtering targets were also formed. Membrane evaluation. The density of the sintered body is generally measured by Archimedes' method and its relative density is calculated. At this time, the theoretical density of the sintered body is calculated by using the average weight of the composition weights of oxides and carbides in the mixed powder before sintering to calculate the relative density. The theoretical density of the sintered body can also be calculated by measuring the crystal phase to be measured by X-ray diffraction of the sintered body, assuming that it is a person constituting the sintered body. In addition, the X-ray diffraction measurement is used to determine the presence of the crystalline phase in the sintered body. For example, the theoretical density of the sintered body can be calculated based on the calculation of the existence ratio of each atom in the sintered body measured by EPMA. The X-ray diffraction measurement was performed by taking a part of the obtained sintered body and measuring it with an X-ray diffractometer according to the following conditions. X-ray: Cu k α line, power • 50kV-200mA, 20 Scanning speed: 4 ° / min, 20 Scanning range: 10 to 100. Gap system (DS-SS-RS): 0.5. -0.5. -0.15mm. The sputtering discharge test is performed using an RF magnetron device under argon pressure -21-(17) (17) 200303931 0.4 Pa, with an input power of 3 00W. Check whether the sputtering target is cracked or damaged or abnormal. Discharge. The phase-change optical recording medium I and the phase-change optical recording medium II produced in Examples 1 to 4, 6, 7, 11, 12, and Comparative Examples 1 and 2 were subjected to initial crystallization of the recording layer in an initializing device. Next, on the trajectory in the field of crystallizing the recording layer, a 0.6 μm long amorphous mark was recorded at a linear velocity of 6 m / sec (recording pitch: 1.2 μm, λ · 68 6ηΝΑ = 0.55). The recording was performed using a laser modulation pattern with additional pulse disconnection as shown in Figure 3, and the pulse interruption power (Poff) and read-in power (Pr) were set to lmW and the peak power width was 50ns. The width is 33ns. The bias power (Pb) is 5mW, the peak power (Pp) is changed to record the amorphous mark, and the Pp when the CNR becomes the maximum is the optimal PP (Pp0). Next, the amorphous mark was recorded with Pb = 5mW and PP = PPG, and the laser beam was irradiated with various powers to eliminate the amorphous mark. At this time, the difference between the carrier levels before and after the cancellation is measured as the elimination rate, and the laser power when the elimination rate becomes the maximum is the optimum Pp (PpQ). Then use Pp as (PpQ-l) mW and Pb as (PbQ-l) mW to record the amorphous label (label length .0.6 μm), and irradiate with laser beams of various powers to eliminate the amorphous label. And eliminated with (Pb 〇-1) mW laser. This recording is performed 20 times per track (this step is hereinafter referred to as an initialization process). Record the amorphous mark (marking length: 0.6 μm) with Pb = Pb () mW and linear velocity 6m / sec on the track after the initializing process, and measure the recording power (Pp) dependence of C NR (hereinafter referred to as the power curve ). In addition, the track of the initializing process is recorded with Pr = lmW, Poff = lrnW, Pp = Pp〇, Pb = Pb〇-22 (18) (18) 200303931 radio frequency recording (recording interval: 1.2 μm), The record indicates that the elimination is performed at a linear speed of 12 m / sec with various elimination powers, and the difference between the carrier levels before and after the elimination is determined, and the maximum rate is defined as the elimination rate. The power curve of the CNR of the phase-change optical recording medium I produced using the sputtering target obtained in Example 1 is shown in FIG. 4. The power curve is defined as the recording sensitivity (Pth) of each phase-change optical recording medium at the intersection point with CNR = 30dB. The sputtering targets of Examples 1 and 2 (Examples 2-1 to 8) were evaluated. The results are shown in Table i. It can be known from Table 1 that any of the sputtering targets of Examples 丨 and 2 can obtain a relative density of more than 70%, and no cracks or breakage will occur during sintering or sputtering. In addition, no abnormal discharge or particles were generated during splashing. The elimination rates are particularly preferably Ta205, Si02, Al203, Ti02, and Nb205.

-23- 200303931

£ Are there any abnormal discharges during splashing? Deer stag 壊 壊 Deer stag Deer stag Deer stag Deer stag Deer stag sintering Dessert sinter stag 戡 壊 壊 壊 # 消除 1 i Elimination rate (line Speed 12m / s) | Media 丨 丨 I____m___ CNJ ① CN c \ i Media I m CD CO CD CO Another 85 Relative density [%] GO GO to 00 § 00 00 Oxide Tβ2〇5 AI2O3 Zr〇2 Si02 Ti02 Nb205 Zn 〇lfl2〇3 Sn02 Sample No. Example 1 Example 2-1 Example 2-2 Example 2-3 Example 2-4 Example 2-5 Example 2-6 Example 2-7 Example 2-8 -24- (20) (20) 200303931 For Example 1, Example 3 (Examples 3 -1 to 8), Comparative Example 1 (Comparative Examples 1-1 to 2), and Comparative Example 2 (Comparative Example 2-1 The results of the evaluation of the sputtering target of) are not shown in Table 2. It can be known from Table 2 that any of the sputtering targets of Examples 1 and 2 can obtain a relative density of more than 70%, and Examples 1 and 3 using carbides in the additive (Example 3 -1 to 8) The sputtering target does not produce cracks or breakage during sintering or sputtering, nor does it generate abnormal discharge or particles during sputtering. In particular, SiC, TaC, TiC, Nb2C, and WC can achieve good results with high sensitivity without reducing the elimination rate. On the other hand, the sputtering target of Comparative Example 1 (Comparative Examples 1 to 2 to 2) with nitride added, when it was sprayed, would be damaged or abnormally discharged, and the recording sensitivity would also be low. The recording target of Example 2 (Comparative Example 2-1) has a reduced sensitivity.

-25- 200303931

CNJ skimming with or without abnormal discharge 1 1 ______________ 壊 鹿 戡 壊 壊 壊 壊 继 #: 有 Whether there are cracks during splashing Condensing deer shoe lasts 1 Whether there are cracks during sintering t_ Deer deer elimination rate (line speed 12m / s) Media II [dB] __ σ > CN 00 CN 〇〇CM CN CN 1〇CNJ LO CN 1〇CNI CM CNJ csi 〇) eg Media I __W_ CO CO 1〇C0 ΙΟ CO 茺 ① CSJ CO CNJ c \ i Recording sensitivity (Pth) Media I [mW] ΙΌ οό CD 00 ΟΟ 00 〇σί N- 00 10.1 10.5 10.2 10.5 12.0 11.5 12.0 Relative density [%] 00 00 ⑦ 00 CO 00 S CO § Additive SiC TaC Tie Nb2C WC ZrC HfC ai4c3 Mn0 2 CeN ZrN 壊 Sample No. Example 1 Example 3-1 Example 3-2 Example 3-3 Example 3-4 Example 3-5 Example 3-6 Example 3-7 Example 3-8 Comparative Example 1_1 Comparative Example 1-2 Comparative Example 2-1 -26- (22) (22) 200303931 For Example 1, Example 4 (Example 4-1 Table 6 shows the evaluation results of the sputtering targets of Comparative Example 2 and Comparative Example 2 (Comparative Examples 2-1 and 2). From Table 3, it can be seen that the removal rate will not decrease if the content of the carbide powder is 20 wt% or less. From the viewpoint of recording sensitivity pth, the content of the carbide powder is preferably 0.1 to 20 wt%, especially 1 to 10 wt%. good. In addition, these sputter targets do not generate cracks or breakage during sintering or spattering, nor do they produce abnormal discharge or particles during spattering.

-27- 200303931

ε splatter 1 whether there is abnormal discharge 1 壊 rub 壊 deer stag stag deer stag deer stag with or without cracks 壊 壊 壊 can 壊 裢 smash sintered 无 scoring 壊 戡 裢 壊 壊 壊 壊 壊 壊 壊 壊 壊 壊 elimination rate (line Speed 12m / s) 1 Media 丨 丨 __m__ CM CD CN σ) CNJ 00 CM CO CM (D CNJ Media 1 1__m___ CO CO CD CO LO 00 ΙΟ CO CN CO i Recording Sensitivity (Pth) Media I i [mW] 12.0 Inch σί Τ Ο) LO 00 * CO od Inch od l〇σί 10.0 12.0 Relative density [%] § Ο) § 00 00 CD 00 CSJ 00 00 CO SiC addition amount [wt%] 〇d ΙΓ > ο LO c \ i in om LO < N Comparative Example 2-1 Example 4-1 Example 4-2 Example 1 Example 4-3 Example 4-4 Example 4-5 Example 4-6 Comparative Example 2-2- 28- (24) (24) 200303931 The evaluation results of the sputtering targets of Example 1, Example 5 (Examples 5-1 to 3), and Comparative Example 3 (Comparative Examples 3 to 1, 2) are shown in the table. 4. It can be seen from Table 4 that the average particle diameter of the mixed powder is 15 μm or less, and a sufficient sintering density can be obtained. No cracks or breakage will occur during sintering or spraying, and no abnormal discharge or particles will be generated during spraying.

-29- (25) 200303931

Abnormal discharge during splashing 1 Roe deer Roe no cracks during splashing 1 Deer congee Roe deer cracking during sintering Dew-like condensation 3 ^ LO CD 00 CD S 00 SS CO m 〇to CN CO LO CO ιό T—Unknown Army Series IK U IK K -30 (26) (26) 200303931 Evaluation results of the sputtering targets of Example 1, Example 6 (Examples 6-1 to 2), and Comparative Example 4 are shown in table 5. From this result, it can be seen that when the temperature reduction rate after the end of sintering is 300 ° C / hr or less, no cracks or breakages occur during sintering or spraying, and no abnormal discharge or particles are generated during spraying.

-31-200303931 s There is no abnormal discharge during spraying Luhan 1 There are no cracks during spraying Luhan «No cracks during sintering 壊 Relative density [%] § 00 〇〇S Cooling speed [° C / hr] 100 200 300 400 Example 1 Example 6-1 Example 6-2 Comparative Example 4 (28) (28) 200303931 For Example 1, Example 7 (Examples 7-1 to 3), Example 8 (Implementation The evaluation results of the sputtering targets of Examples 8 to 1 to 4) and Comparative Example 5 are shown in Table 6. From the results, it can be seen that when the sintering temperature is above 900 ° C, a sufficient sintering density can be obtained, and in particular, a higher sintering density can be obtained by the hot pressing method. Increasing the sintering temperature to more than 900 ° C will not cause cracks or breakage during sintering or spraying, and will not generate abnormal discharge or particles during spraying. Further, the sputtering target (Example 7-2, Example 8-3) obtained at a sintering temperature of 1,300 ° C by a hot pressing method or an atmospheric pressure sintering method was measured by X-ray diffraction to confirm the formation of TaC. The phase-change optical recording medium produced using the sputtering target confirming the generation of TaC confirmed that the erasure rate was relatively low in either of the phase-change optical recording medium I and the phase-change optical recording medium II.

-33- (29) 200303931 Elimination rate [dB] (Line speed 12m / s) Media II 1 CM CD CM 00 CNI σ > CNJ 00 CNI Media I 1 CD CO CO CO ΙΩ 00 CD 00 LO C0 TaC Dew condensing with or without abnormal discharge Deer following Deer Deer Deer Deer with or without cracks during splatter 壊 壊 鹿 壊 #: Deer soil 戡 with or without cracks during sintering 壊 壊 壊 壊 壊 壊 Relative density of rattan 雔 壊 [% ] 00 00 CNJ h- C0 sintering temperature [° c] 800 900 1100 1200 1300 900 1100 1200 1300 sintering method hot pressing hot pressing hot pressing hot pressing normal pressure furnace normal pressure furnace normal pressure furnace normal pressure furnace comparative example 5 implementation Example 7-1 Example 1 Example 7-2 Example 7-3 Example 8-1 Example 8-2 Example 8-3 Example 8-4

-34- (30) (30) 200303931 The sputtering targets of Examples 1 and 9 (Examples 9-1, 2) were evaluated. The results are shown in Table 7. From the results, it can be seen that a sufficient sintering density can be obtained when the pressure during sintering is 100 kg / Cm2 or more, and no cracks or breakages are generated during sintering or spraying, and abnormal discharge or particles are not generated during spraying.

-35- 200303931 ίΜ There is no abnormal discharge during spraying. Deer stag has no cracks during spraying. There are no cracks during sintering. Relative density _____ [% J___ 〇〇§8 Pressure [kg / cm2] 100 150 200 Implementation Example 9-1 Example 9-2 Example 1 (32) (32) 200303931 The sputtering targets of Example 1, Example 10 (Example 1 0-1, 2) and Comparative Example 6 were evaluated, and the results were evaluated. Shown in Table 8. From the results, it can be seen that the holding time during sintering is more than 0.5 hours, and a sufficient sintering density can be obtained. There will be no cracks or breakage during sintering or spraying, and no abnormal discharge or particles will be generated during spraying. .

-37- (33) 200303931

Is there an abnormal discharge during spraying? Deer stag has no cracks during splashing. Deer stag has no cracks during sintering. 00 CD CD 00 00 Se Disk writing UO Γ \ Ί dd tN τ- 〇 CD x ~ 挈 集集 JLJ鹣 舾 U (34) (34) 200303931 The sputtering targets of Example 1, Example 11 and Example 12 were evaluated. The results are shown in Table 9. From the results, it can be known that any of these sputtering targets can obtain a sufficient sintering density, and no cracks or breakage will occur during sintering or sputtering, and no abnormal discharge or particles will be generated during sputtering. A phase change optical recording medium made using a sputtering target containing an oxide of indium or chromium in addition to an oxide of tantalum as a sintered body constituting the oxide, and recorded on the phase change optical recording medium I and phase change optical recording When any of the media II was compared with a phase change optical recording medium produced using a sputtering target containing only a giant oxide as a constituent sintered body of the oxide, it was confirmed that the recording sensitivity was further improved.

-39- (35) 200303931 Elimination rate (line speed 12m / s) Media 丨 丨 dB 丄 ― CN cn CM CVJ Media I Just CD CO to CO u〇CO Recording Sensitivity (Pth) Media I [mW] m 00 to [Bub] Are there any abnormal discharges during spraying? No cracks during spraying. No cracks during sintering. Deer's relative density [%] 00 00 CO 〇〇carbide 〇CO 〇 < y5 SiC oxide ② Snow ΙΠ2 〇3 Zr02 oxide ① T32〇5 Tβ2 05 Ta2 05 Example 1 Example 11 Example 12 (36) (36) 200303931 As described above, a multilayer film including a protective layer, an interface layer, and a recording layer is formed on the substrate. In order to record information using the reversible phase change between the crystalline phase and the amorphous phase of the recording layer, the phase change is eliminated in the optical recording medium by using one or more substances selected from oxides and one or more substances selected from carbides. It is composed of a material whose content of the carbide is 0.1% by weight or more and 20% by weight or less, forming a protective layer or an interface layer, and obtaining a phase change optical recording medium capable of rewriting at a line speed of 12 m / sec or more. In addition, the oxide is preferably one or more oxides selected from the group consisting of giant, silicon, aluminum, titanium, niobium, hafnium, zinc, indium, and tin, and the carbide is one or more oxides selected from the group consisting of silicon, giant, titanium, niobium, and tungsten. Carbide is preferred. In particular, a protective layer or an interface layer is formed of a material containing a giant oxide such as Ta205 and a silicon carbide such as SiC, and the silicon carbide content is 0.1% by weight to 20% by weight, and the erasing rate characteristics and recording sensitivity can be obtained. More superior phase change optical recording media. In addition to giant oxides such as Ta205, oxides containing indium such as ln203, or oxides of zirconium such as Zr02, and the silicon carbide content of silicon such as SiC is 0.1 wt% to 20 wt%, to form a protective layer or The interface layer can obtain a phase-change optical recording medium with superior recording sensitivity. The layer formed to protect the recording layer, promote the crystallization of the recording layer, and prevent the diffusion of atoms to the recording layer, etc., can not only form a single layer of a protective layer, but also share these functions by forming an interface layer + a protective layer. By expanding the design freedom of the phase change optical recording medium, it is possible to obtain a phase change optical recording medium having superior recording and reproduction characteristics, durability, and reliability. The thickness of such an interface layer is preferably from 0.1 to 20 nm, more preferably from 0.2 to 10 nm, and most preferably from 0.2 to 2.5 nm. 0-41-(37) (37) 200303931 [Effects of the Invention] The Splash of the Invention The target is a high-speed and stable film-former that does not suffer damage, breakage, or abnormal discharge during sputtering. Therefore, using the sputtering target of the present invention, a phase-change optical recording medium having excellent recording and reproduction characteristics can be obtained with high productivity. [Brief description of the drawings] [Fig. 1] Fig. 1 shows a temperature mode and a pressurizing mode when the examples and comparative examples are sintered. [Fig. 2] Fig. 2 is a cross-sectional view showing the structure of the phase-change optical recording medium I and the phase-change optical recording medium 11 produced using the examples and comparative examples. (A) Phase change optical recording medium I, (2) Phase change optical recording medium II. [Figure 3] Figure 3 shows the laser modulation mode used in the evaluation of the phase-change optical recording medium produced in the examples and comparative examples. [Fig. 4] Fig. 4 shows the CNR power curve of the phase-change optical recording medium I made in Example 1. [Symbol description] 3 11 '321: Substrate-42- (38) (38) 200303931 312, 3 22: First protective layer 3 23: First interface layer 3 1 3, 3 2 4: Recording layer 3 2 5. • 2nd interface layer 3 14, 3 26: 2nd protective layer 3 15 '3 2 7: reflective layer 316, 328: protective coating layer

-43-

Claims (1)

(1) (1) 200303931 Pickup, patent application scope 1. A sputtering target, characterized by being composed of one or more substances selected from oxides and one or more substances selected from carbides, and the carbide content is O. It is composed of sintered body having a relative density of 70% or more and 1wt% or more and 20wt% or less. 2. The sputtering target according to item 1 of the scope of patent application, wherein the oxide constituting the sintered body is one or more oxides selected from the group consisting of tantalum, silicon, aluminum, titanium, niobium, chromium, zinc, indium, and tin. 3. The sputtering target according to item 1 or 2 of the scope of patent application, wherein the carbide constituting the sintered body is one or more kinds of carbides selected from silicon, giant, titanium, niobium and tungsten. 4. The sputtering target according to item 1 of the patent application scope, wherein the carbide constituting the sintered body is a silicon carbide. 5. The sputtering target according to item 2 of the scope of patent application, wherein the carbide constituting the sintered body is a silicon carbide. 6. The sputtering target according to item 4 or 5 of the patent application scope, wherein the sintering system is substantially free of carbides of elements other than Si. 7. · A sputtering target is a sintered body containing giant oxide and silicon carbide, and the silicon carbide content in the sintered body is 0.1 wt% or more and 20 wt% or less, and the relative density is 70% or more of sintered body. 8. The sputtering target according to item 7 of the patent application scope, wherein the sintering system is substantially free of carbides of elements other than Si. 9. A method for manufacturing a sputtering target, the method comprising -44- (2) (2) 200303931 step of sintering a mixed powder obtained by mixing a raw material powder of an oxide and a carbide to obtain a sintered body. In the method of a sputtering target composed of a sintered body composed of a substance selected from an oxide and one or more substances selected from a carbide, the aforementioned mixed powder is a mixed powder having an average particle diameter of 15 μm, and Carbide content is 0.1 wt% or more and 20 wt% or less, and the sintering temperature is 900 ° C or more, the holding time at the sintering temperature is more than 30 minutes', and the sintering temperature is 300 ° C / hr or less, and the sintering is performed. 10 — A method for manufacturing a sputtering target, which comprises a step of sintering a mixed powder obtained by mixing raw material powders of tantalum oxide and silicon carbide to obtain a sintered body. The sputtering target is composed of an oxide containing tantalum and The sintered body of silicon carbide is composed of a mixed powder having an average particle size of 15 μm or less as the aforementioned mixed powder, and the content of silicon carbide in the aforementioned mixed powder It is 0.1 to 20 wt%, and sintered at a sintering temperature of 900 t: or more, a holding time at the sintering temperature of 30 minutes or more, and a temperature lowering speed of 300 ° C / hr or less after the sintering is completed. 1 1. The method for manufacturing a sputtering target according to item 10 of the scope of patent application, wherein the sintering is performed at a sintering temperature of 900 ° C or higher and 1200 ° C or lower. -45-