Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C1/00—Making non-ferrous alloys
  • C22C1/02—Making non-ferrous alloys by melting
  • C22C1/026—Alloys based on aluminium
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C21/00—Alloys based on aluminium
  • C22C21/02—Alloys based on aluminium with silicon as the next major constituent
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
  • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
  • C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
  • C22F1/043—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with silicon as the next major constituent
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W72/00—Interconnections or connectors in packages
  • H10W72/50—Bond wires
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N2223/00—Investigating materials by wave or particle radiation
  • G01N2223/60—Specific applications or type of materials
  • G01N2223/611—Specific applications or type of materials patterned objects; electronic devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
  • G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
  • G01N23/225—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion
  • G01N23/2251—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion using incident electron beams, e.g. scanning electron microscopy [SEM]
  • G01N23/2252—Measuring emitted X-rays, e.g. electron probe microanalysis [EPMA]
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W72/00—Interconnections or connectors in packages
  • H10W72/01—Manufacture or treatment
  • H10W72/015—Manufacture or treatment of bond wires
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W72/00—Interconnections or connectors in packages
  • H10W72/01—Manufacture or treatment
  • H10W72/015—Manufacture or treatment of bond wires
  • H10W72/01551—Changing the shapes of bond wires
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W72/00—Interconnections or connectors in packages
  • H10W72/50—Bond wires
  • H10W72/521—Structures or relative sizes of bond wires
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W72/00—Interconnections or connectors in packages
  • H10W72/50—Bond wires
  • H10W72/551—Materials of bond wires
  • H10W72/552—Materials of bond wires comprising metals or metalloids, e.g. silver
  • H10W72/5524—Materials of bond wires comprising metals or metalloids, e.g. silver comprising aluminium [Al]

Definitions

• the present invention relates to an Al alloy bonding wire. It also relates to a semiconductor device that includes the Al alloy bonding wire.
• electrodes formed on a semiconductor chip are connected to electrodes on a lead frame or substrate by bonding wire.
• aluminum (Al) bonding wire is mainly used, with wire diameters ranging from ⁇ 300 ⁇ m to ⁇ 600 ⁇ m.
• silicon (Si) is often used as the material for the semiconductor chip, and Al-Si alloys or Al-Cu alloys are often used as the material for the electrodes formed on the semiconductor chip.
• Power semiconductor devices that use Al bonding wire are often used in high-power equipment such as air conditioners and solar power generation systems, and in-vehicle semiconductor devices.
• Wedge bonding is a method in which ultrasonic waves and a load are applied to the Al bonding wire via a metal jig to destroy the surface oxide film of the bonding wire material and the electrode material, exposing the new surface and performing solid-phase diffusion bonding. If a bonding defect occurs during bonding, such as the Al bonding wire peeling off from the electrode, it can lead to product defects and reduced manufacturing yields, so it is necessary to obtain good bonding strength at each bonding point. If strong ultrasonic waves or loads are applied to the first bonding point to obtain good bonding strength, the semiconductor chip may be damaged. Therefore, in addition to obtaining good bonding strength, it is necessary to suppress damage to the semiconductor chip in the first bonding.
• Next-generation power semiconductor devices are required to operate stably for a long period of time compared to general-purpose power semiconductor devices.
• Power semiconductor devices operate by repeatedly turning current on and off. When current is supplied to a Si semiconductor chip via an Al bonding wire, the temperature of the first junction rises. On the other hand, when the current supply is stopped, the temperature of the first junction drops. In this way, the first junction repeatedly rises and falls in temperature during operation of the power semiconductor. As a result, the first junction is repeatedly subjected to thermal stress due to the difference in thermal expansion between the Al bonding wire and the semiconductor chip.
• next-generation power semiconductors are required to improve the junction life (hereinafter also referred to as "temperature cycle reliability") associated with the rise and fall of temperature of the first junction.
• an Al bonding wire In response to the demand for temperature cycle reliability, an Al bonding wire has been proposed that focuses on improving mechanical strength. As a method for improving the mechanical properties of Al bonding wire, a method of adding specific elements to Al has been proposed.
• Patent Document 1 discloses a bonding wire made of an Al alloy containing at least magnesium (Mg) and silicon (Si) and having a total content of Mg and Si of 0.03% by mass to 0.3% by mass. This patent document discloses that the decrease in the bonding strength of the first bonding part in a thermal cycle test in the temperature range of 70°C to 120°C is delayed due to the effect of increasing the strength by solid solution strengthening of Mg and Si and the effect of suppressing crack growth by precipitated magnesium silicide (Mg 2 Si).
• Patent Document 2 discloses a bonding wire made of an alloy containing 0.01-0.2 mass% iron (Fe), 1-20 mass ppm silicon (Si), and the remainder being Al with a purity of 99.997 mass% or more, with the amount of Fe in solid solution being 0.01-0.06%, the amount of Fe precipitated being 7 times or less the amount of Fe in solid solution, and a fine structure with an average crystal grain size of 6-12 ⁇ m.
• This patent document discloses that by uniformly dispersing intermetallic compound particles of Fe and Al in Al to improve the mechanical strength of the matrix and further by refining the recrystallized grains, it is possible to suppress a decrease in the bonding strength of the first bonding part in a thermal shock test in a temperature range of -50°C to 200°C.
• Patent Document 3 discloses a bonding wire made by melting an Al-Si alloy containing 0.1 to 5 mass% silicon (Si) with the remainder being Al and impurities, then ejecting and quenching the melted Al-Si alloy to form it into a fine wire. This patent document discloses that mechanical strength is improved by quenching the molten Al-Si alloy to finely and uniformly disperse the Si.
• JP 2014-131010 A JP 2014-129578 A Japanese Patent Application Laid-Open No. 59-57440
• the aluminum bonding wire used in next-generation power semiconductor devices is required to have high temperature cycle reliability at the first joint so that it can withstand long-term use, and to provide good bonding properties at the first joint.
• Next-generation power semiconductor devices are required to be able to withstand longer periods of use than general-purpose power semiconductor devices.
• the temperature of the first junction rises and falls repeatedly during operation of the power semiconductor device.
• the Al bonding wire has a larger linear expansion coefficient than the semiconductor chip, thermal stress occurs at the first junction due to the difference in linear expansion coefficient between the two, and there was a problem that the Al bonding wire eventually breaks down due to fatigue.
• the temperature cycle test is one of the tests that accelerates evaluation of the life (temperature cycle reliability) of the junction as the temperature of the first junction rises and falls.
• the Al bonding wire used in next-generation power semiconductor devices is required to have excellent temperature cycle reliability in the temperature cycle test.
• the objective of the present invention is to provide an Al bonding wire that has excellent temperature cycle reliability and good 1st bondability.
• the present invention includes the following.
• the average ratio (a / b) of the length (a) of the Si phase in the L cross section in the wire central axis direction to the length (b) in the direction perpendicular to the wire central axis is 1.3 to 3.2.
• the present invention provides an Al alloy bonding wire that has excellent temperature cycle reliability and good first bondability.
• FIG. 1 is a schematic diagram for explaining a measurement target surface (inspection surface) when measuring the average diameter and crystal orientation of the Si phase of an Al alloy bonding wire.
• the measurement target surface is a cross section (L cross section) in the central axis direction including the wire central axis of the Al alloy bonding wire.
• FIG. 2 is a schematic diagram for explaining the length (a) of the Si phase in the L cross section in the direction of the central axis of the wire and the length (b) in the direction perpendicular to the central axis of the wire.
• the Al alloy bonding wire of the present invention (hereinafter, simply referred to as "the wire of the present invention” or “wire”) is an Al alloy bonding wire containing 3.0 mass% to 10.0 mass% of Si, and is characterized in that the average diameter of the Si phase in a cross section (L cross section) in the central axis direction including the wire central axis of the wire is 0.8 ⁇ m to 5.5 ⁇ m.
• the wire central axis of the Al alloy bonding wire and the cross section (L cross section) in the central axis direction including the wire central axis of the wire are as described below in the section "(Method of measuring the average diameter of the Si phase and the shape of the Si phase)" with reference to FIG. 1.
• the inventors have conducted extensive research to solve the above problems and have found that an Al alloy bonding wire containing 3.0% to 10.0% by mass of Si, in which the average diameter of the Si phase in the L-section is 0.8 ⁇ m to 5.5 ⁇ m, can improve temperature cycle reliability.
• Such a wire of the present invention significantly contributes to achieving the temperature cycle reliability required for next-generation power semiconductor devices.
• the wire of the present invention has a hypoeutectic composition containing 3.0% to 10.0% by mass of Si, and is composed of an ⁇ phase in which Si is dissolved in Al, and a Si phase.
• the reason why the wire of the present invention can provide good temperature cycle reliability is presumed to be as follows. First, since the linear expansion coefficient of the Si phase is smaller than that of Al, by containing Si at 3.0 mass% to 10.0 mass%, the linear expansion coefficient of the Al alloy bonding wire is reduced, and the thermal stress generated during the temperature cycle test is reduced. Furthermore, by controlling the average diameter of the Si phase in the L cross section of the Al alloy bonding wire to 0.8 ⁇ m or more, the strength of the ⁇ phase due to the precipitation strengthening of the Si phase can be suppressed. This has the effect of preventing cracks from progressing in the Al alloy electrode during the temperature cycle test.
• the wire of the present invention can exhibit good reliability by appropriately controlling multiple factors that contribute to improving the temperature cycle reliability.
• the Si concentration in the Al alloy bonding wire of the present invention is 3.0 mass% or more, preferably 4.0 mass% or more, more preferably 4.2 mass% or more, 4.4 mass% or more, 4.5 mass% or more, 4.6 mass% or more, or 4.8 mass% or more.
• the hardness of the Al alloy bonding wire is excessive, damage to the semiconductor chip is likely to occur during the first bonding under the commonly used ultrasonic and load bonding conditions.
• the Si concentration in the Al alloy bonding wire of the present invention is 10 mass% or less, preferably 8.0 mass% or less or 7.0 mass% or less, more preferably 6.8 mass% or less, 6.6 mass% or less, or 6.5 mass% or less.
• the average diameter of the Si phase in the L-section of the wire of the present invention is 0.8 ⁇ m or more, preferably 1.2 ⁇ m or more or 1.4 ⁇ m or more, more preferably 1.5 ⁇ m or more, 1.6 ⁇ m or more, or 1.8 ⁇ m or more.
• the Si phase becomes too coarse, the number density of the Si phase decreases, making it difficult to stably obtain the crack propagation suppression effect of the Si phase.
• the average diameter of the Si phase in the L-section of the wire of the present invention is 5.5 ⁇ m or less, preferably 5.0 ⁇ m or less or 4.5 ⁇ m or less, more preferably 4.0 ⁇ m or less.
• an ICP (Inductively Coupled Plasma) emission spectrometer or an ICP mass spectrometer can be used. If elements derived from atmospheric contaminants such as oxygen or carbon are adsorbed on the surface of the wire, it is effective to wash the wire with an acid or alkali depending on the adsorbed substance before analysis.
• a method for measuring the diameter of the Si phase in the L cross section of the wire of the present invention will be described.
• a method for measuring the diameter of the Si phase in the L cross section for example, a method using a reflected electron image by a field emission scanning electron microscope (FE-SEM) can be mentioned.
• FE-SEM field emission scanning electron microscope
• a specific measurement method will be described below.
• a reflected electron image of the L cross section of the wire is obtained using an FE-SEM.
• the ⁇ phase and the Si phase are observed with different contrasts, and the Si phase is extracted by a binarization process using this contrast.
• the brightness value of the reflected electron image of the acquired L cross section is normalized to a range of 0 to 1, and the threshold value is determined in the range of 0.45 to 0.95 to binarize it.
• the threshold value is appropriately determined so that the Si phase and the ⁇ phase can be distinguished.
• the circle equivalent diameter is defined as the diameter of the Si phase, and the arithmetic average value of the diameters of each Si phase is defined as the average diameter. Therefore, in one embodiment, the average diameter of the Si phase in the L cross section of the wire of the present invention is calculated by the following procedures (1) to (3).
• a backscattered electron image of the L-section of the wire is obtained using an FE-SEM.
• the Si phase is extracted by binarization processing that utilizes the contrast of the acquired backscattered electron image.
• Image analysis is performed on each of the extracted Si phases to determine the circle equivalent diameter, and the circle equivalent diameters are arithmetically averaged to calculate the average diameter of the Si phases.
• the Si concentration may be measured by EDS to identify the Si phase in order to set a threshold value or, if necessary, to distinguish the Si phase from foreign matter or scratches.
• the average diameter of the Si phase when calculating the average diameter of the Si phase, only Si phases with a diameter of 0.5 ⁇ m or more are considered. This makes it possible to accurately determine whether the requirements for the average diameter of the Si phase suitable for satisfying the temperature cycle reliability required for next-generation power semiconductor devices are met.
• the measurement area for the average diameter of the Si phase was determined to be a length in the direction of the central axis of the wire of 100 ⁇ m or more and less than 400 ⁇ m, and the entire wire was included in the direction perpendicular to the central axis of the wire.
• the inventors in the course of their investigations into an Al alloy bonding wire containing 3.0% by mass or more and 10.0% by mass or less of Si and having an average diameter of the Si phase in the L cross section of 0.8 ⁇ m or more and 5.5 ⁇ m or less, have found that the shape of the Si phase in the L cross section also affects the high-speed temperature cycle reliability.
• the high-speed temperature cycle reliability can be improved by setting the average value of the ratio (a/b) of the length (a) of the Si phase in the L cross section in the wire central axis direction to the length (b) in the direction perpendicular to the wire central axis of 1.3 to 3.2. Further explanation will be given with reference to FIG. 2.
• FIG. 2 Further explanation will be given with reference to FIG. 2.
• FIG. 2 is a schematic diagram showing the Si phase in the L cross section of the wire, with the wire central axis direction corresponding to the horizontal direction (left-right direction) of FIG. 2 and the direction perpendicular to the wire central axis corresponding to the vertical direction (up-down direction) of FIG. 2.
• the above-mentioned "length in the wire central axis direction (a)" refers to the maximum dimension of the Si phase in the wire central axis direction, which corresponds to the dimension indicated by the symbol a in FIG. 2.
• the above-mentioned "length (b) in the direction perpendicular to the central axis of the wire” refers to the maximum dimension of the Si phase in the direction perpendicular to the central axis of the wire, and corresponds to the dimension indicated by the symbol b in FIG. 2.
• the ratio (a/b) of the length (a) of the Si phase in the L cross section in the direction of the central axis of the wire to the length (b) in the direction perpendicular to the central axis of the wire will also be referred to simply as the "ratio (a/b) of the Si phase in the L cross section.”
• the reason why the high-speed temperature cycle reliability is improved by controlling the average value of the Si phase ratio (a/b) in the L cross section in the wire of the present invention is presumed to be as follows. During the high-speed temperature cycle test, cracks propagate inside the Al alloy bonding wire and lead to destruction. Cracks tend to propagate along the central axis of the wire or a direction close to it, and it is considered effective to reduce the thermal stress in the central axis of the wire.
• the linear expansion coefficient in the central axis of the wire can be reduced, and as a result, the thermal stress in the central axis of the wire applied to the Al alloy bonding wire can be reduced.
• the effect of reducing the thermal stress that causes fatigue failure in the Al alloy bonding wire in the central axis of the wire can be synergistically enhanced by containing 3.0 mass% to 10.0 mass%, and the average diameter of the Si phase in the L cross section is 0.8 ⁇ m to 5.5 ⁇ m, and further controlling the average value of the Si phase ratio (a/b) in the L cross section to 1.3 to 3.2.
• the time of exposure to high temperatures is shorter than in the temperature cycle test, so recovery and recrystallization are less likely to occur, and plastic strain, which is the driving force for crack propagation, is more likely to accumulate.
• the Si phase may contain a Si phase with a ratio (a/b) of less than 1.3, or a phase with a ratio (a/b) of more than 3.2.
• the average value of the Si phase ratio (a/b) in the L cross section of the wire of the present invention is more preferably 1.4 or more.
• the average value of the Si phase ratio (a/b) in the L cross section of the wire of the present invention is preferably 3.2 or less, and more preferably 2.8 or less.
• a method for measuring the length (a) of the Si phase in the wire central axis direction and the length (b) in the direction perpendicular to the wire central axis in the L cross section of the wire of the present invention will be described.
• a backscattered electron image of the L cross section is obtained by FE-SEM, and the Si phase is extracted by binarization processing using the contrast of the obtained backscattered electron image.
• the guideline for setting the threshold value for the binarization processing and, if necessary, the Si phase may be identified by measuring the Si concentration using EDS in order to distinguish the Si phase from foreign matter or scratches are also as described above for the method for measuring the diameter of the Si phase.
• the length (a) in the wire central axis direction and the length (b) in the direction perpendicular to the wire central axis are calculated using image analysis software (Esprit, etc., manufactured by Bruker).
• the average value of the ratio (a/b) of the Si phase in the L cross section is the arithmetic average value of the ratio (a/b) calculated for each Si phase.
• the average value of the Si phase ratio (a/b) in the L cross section of the wire of the present invention is calculated by the following steps (1) to (3).
• a backscattered electron image of the L-section of the wire is obtained using an FE-SEM.
• the Si phase is extracted by binarization processing that utilizes the contrast of the acquired backscattered electron image.
• Image analysis is performed on each extracted Si phase to measure the length (a) in the direction of the central axis of the wire and the length (b) in the direction perpendicular to the central axis of the wire to obtain the ratio (a/b), and the ratios are arithmetically averaged to calculate the average ratio (a/b) of the Si phase.
• the ratio (a/b) of the Si phase in the L cross section when calculating the ratio (a/b) of the Si phase in the L cross section, only Si phases with a diameter (equivalent circle diameter) of 0.5 ⁇ m or more are considered. This makes it possible to accurately determine whether the requirements related to the ratio (a/b) of the Si phase in the L cross section, which is suitable for improving high-speed temperature cycle reliability, are met.
• the measurement area was determined so that the length in the direction of the central axis of the wire was 100 ⁇ m or more and less than 400 ⁇ m, and the entire wire was included in the direction perpendicular to the central axis of the wire.
• the average diameter of the ⁇ phase in the L cross section is preferably 5 ⁇ m or more and 50 ⁇ m or less.
• the inventors have found that by having the average diameter of the ⁇ phase in the L cross section be in the range of 5 ⁇ m or more and 50 ⁇ m or less, the variation in the bonding strength in the 2nd bond can be reduced. This is thought to be because the effect of promoting uniform deformation of the wire by containing a predetermined concentration of Si and controlling the average diameter of the Si phase in the L cross section to a predetermined range, and the effect of reducing the variation in the mechanical strength in the direction perpendicular to the central axis of the wire by setting the average diameter of the ⁇ phase in the L cross section to be in the range of 5 ⁇ m or more and 50 ⁇ m or less, work synergistically.
• the average diameter of the ⁇ phase in the L cross section of the wire of the present invention is more preferably 10 ⁇ m or more, and even more preferably 12 ⁇ m or more, 14 ⁇ m or more, or 15 ⁇ m or more.
• the upper limit of the average diameter of the ⁇ phase in the L cross section is more preferably 45 ⁇ m or less, and even more preferably 40 ⁇ m or less, 38 ⁇ m or less, 36 ⁇ m or less, or 35 ⁇ m or less.
• a method for measuring the diameter of the ⁇ phase in the L cross section of the wire of the present invention will be described.
• a method of combining information on the Al concentration obtained by SEM-EDS and information on the crystal orientation obtained by electron backscattered diffraction (EBSD) can be used.
• the L cross section of the wire is used as the inspection surface, and the concentration measurement of Al and Si using EDS and the crystal orientation analysis using EBSD are performed simultaneously. Then, for the region identified as the ⁇ phase from the EDS measurement results, the crystal orientation can be analyzed by using the analysis software attached to the device.
• the average diameter of the ⁇ phase in the L cross section of the wire of the present invention is calculated by the following steps (1) to (3). (1) The L-section of the wire is used as the inspection surface, and the Al and Si concentrations are measured using EDS and the crystal orientation is analyzed using EBSD at the same time.
• the crystal orientation is analyzed, and if the orientation difference between the measurement points is 15° or more, it is determined to be a grain boundary, and the circle equivalent diameter of each crystal grain is calculated.
• the circle equivalent diameters of each crystal grain are arithmetically averaged to calculate the average diameter of the ⁇ phase.
• the measurement area was determined so that the length in the direction of the central axis of the wire was 100 ⁇ m or more and less than 400 ⁇ m, and the entire wire was included in the direction perpendicular to the central axis of the wire.
• the orientation ratio of the crystal orientation ⁇ 110> which has an angular difference of 15° or less with respect to the central axis direction of the wire, is 30% to 80%.
• the orientation ratio of such a crystal orientation ⁇ 110> is also referred to as "the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section".
• loop straightness is improved by having an orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of 30% or more and 80% or less. This is thought to be because the effect of promoting uniform deformation of the wire by containing a predetermined concentration of Si and controlling the average diameter of the Si phase in the L cross section within a predetermined range works synergistically with the effect of reducing the variation in mechanical strength in the central axis direction of the wire by having an orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of 30% or more and 80% or less.
• the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of the wire of the present invention is more preferably 35% or more, and even more preferably 40% or more, 45% or more, or 50% or more.
• the upper limit of the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section is preferably 80% or less, and more preferably 78% or less, 76% or less, or 75% or less.
• the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of the wire of the present invention a method of combining information on the concentration of Al and Si obtained by SEM-EDS and information on the crystal orientation obtained by EBSD can be used.
• the L cross section of the wire is used as the inspection surface, and the concentration measurement of Al and Si using EDS and the crystal orientation analysis using EBSD are performed simultaneously.
• the orientation ratio of the crystal orientation ⁇ 110> of the Si phase can be calculated by using the analysis software attached to the device.
• the orientation ratio of the crystal orientation ⁇ 110> calculated as the population of the area of only the crystal orientation that could be identified based on a certain reliability within the measurement area was defined as the orientation ratio of the crystal orientation ⁇ 110>.
• the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of the wire of the present invention is calculated by the following procedures (1) and (2).
• the L-section of the wire is used as the inspection surface, and the Al and Si concentrations are measured using EDS and the crystal orientation is analyzed using EBSD at the same time.
• the crystal orientation is analyzed, and the orientation ratio of the Si phase crystal orientation ⁇ 110> is calculated.
• the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section was determined as the arithmetic average of the orientation ratio values obtained by measuring three or more locations.
• the measurement area from the viewpoint of ensuring the objectivity of the measurement data, it is preferable to obtain measurement samples from the bonding wire to be measured at intervals of 1 m or more in the direction of the central axis of the wire and provide them for measurement.
• the measurement area for the crystal orientation using the EBSD method was determined to be a length in the direction of the central axis of the wire of 100 ⁇ m or more and less than 400 ⁇ m, and to include the entire wire in the direction perpendicular to the central axis of the wire.
• the wire of the present invention may further contain at least one of Ni, Pd and Pt in a total amount of 3 ppm by mass or more and 150 ppm by mass or less.
• the inventors have found that the corrosion resistance in a high-temperature, high-humidity environment can be improved by including at least one of Ni, Pd, and Pt in a total amount of 3 ppm by mass or more and 150 ppm by mass or less.
• the reason for this is not clear, but it is thought that the effect of improving the corrosion resistance in a high-temperature, high-humidity environment by including a certain concentration of Si is synergistically enhanced by including at least one of Ni, Pd, and Pt in a total amount of 3 ppm by mass or more and 150 ppm by mass or less.
• the total concentration of Ni, Pd, and Pt in the wire of the present invention is preferably 3 mass ppm or more, more preferably 5 mass ppm or more, 6 mass ppm or more, 8 mass ppm or more, or 10 mass ppm or more, and the upper limit is preferably 150 mass ppm or less, more preferably 145 mass ppm or less, or 140 mass ppm or less.
• the aluminum raw material for manufacturing the wire of the present invention it is preferable to use Al with a purity of 4N (Al: 99.99% by mass or more), and more preferable to use Al with a low impurity content of 5N (Al: 99.999% by mass or more).
• the remainder of the wire of the present invention may contain elements other than Al, as long as the effect of the present invention is not hindered.
• the content of Al is not particularly limited as long as the effect of the present invention is not hindered, but is preferably 90% by mass or more, more preferably 92% by mass or more, 92.5% by mass or more, or 93% by mass or more, and even more preferably 93.5% by mass or more, 94% by mass or more, 94.5% by mass or more, 94.6% by mass or more, 94.8% by mass or more, or 95% by mass or more.
• the remainder of the wire of the present invention consists of Al and inevitable impurities. Therefore, in a preferred embodiment, the wire of the present invention consists of Al, Si, and inevitable impurities. In another preferred embodiment, the wire of the present invention consists of Al, Si, one or more of Ni, Pd, and Pt, and inevitable impurities.
• the wire of the present invention does not have a coating on the outer periphery of the wire that is primarily made of a metal other than Al.
• a coating that is primarily made of a metal other than Al refers to a coating that contains 50 mass% or more of a metal other than Al.
• the wire of the present invention satisfies both good temperature cycle reliability and good bondability at the 1st bond, and also provides good high-speed temperature cycle reliability, good bond strength at the 2nd bond, loop straightness, and high corrosion resistance in high-temperature, high-humidity environments. Therefore, the bonding wire of the present invention can be suitably used as an Al alloy bonding wire for semiconductor devices, particularly as an Al alloy bonding wire for power semiconductor devices.
• the wire diameter of the wire of the present invention is not particularly limited and may be appropriately determined depending on the specific purpose, but is preferably 50 ⁇ m or more, 60 ⁇ m or more, 80 ⁇ m or more, 100 ⁇ m or more, 120 ⁇ m or more, 140 ⁇ m or more, or 150 ⁇ m or more.
• the upper limit of the wire diameter is not particularly limited and may be, for example, 600 ⁇ m or less, 550 ⁇ m or less, or 500 ⁇ m or less.
• the Al and alloying elements used as raw materials preferably have a high purity.
• the purity of Al is preferably 99.99% by mass or more, with the remainder being composed of inevitable impurities.
• the purity of Si, Ni, Pd, and Pt used as alloying elements is preferably 99.9% by mass or more, with the remainder being composed of inevitable impurities.
• the Al alloy used for the bonding wire can be produced by loading the Al raw material and the raw material of the alloying elements into a graphite or alumina crucible processed to obtain a cylindrical ingot, and melting it using an electric furnace or a high-frequency heating furnace.
• the diameter of the cylindrical ingot is preferably ⁇ 6 mm or more and less than 8 mm in consideration of the processability in the subsequent processing steps.
• the atmosphere in the furnace during melting is preferably an inert atmosphere or a reducing atmosphere to prevent excessive oxidation of Al and other elements constituting the wire.
• the maximum temperature of the molten metal during melting is preferably in the range of 700 ° C. or more and less than 1050 ° C. to prevent the incorporation of impurity elements from the crucible into the molten metal while ensuring the fluidity of the molten metal.
• the cooling method after melting can be water cooling, furnace cooling, air cooling, or the like.
• the cylindrical ingot obtained by melting is subjected to a homogenization process, and then wire drawing using a die and intermediate heat treatment are repeated to produce wire of the desired diameter. After wire drawing, the wire is subjected to final heat treatment in an electric furnace so that it can be used as Al alloy bonding wire.
• the average diameter of the Si phase in the L cross section In order to control the average diameter of the Si phase in the L cross section to within the range of 0.8 ⁇ m to 5.5 ⁇ m, it is effective to control manufacturing conditions such as the homogenization treatment conditions, wire drawing conditions, intermediate heat treatment conditions, and final heat treatment conditions. During wire drawing, it is effective to use a lubricating liquid to ensure lubrication at the contact interface between the wire and the die.
• manufacturing conditions for controlling the average diameter of the Si phase in the L cross section to within the range of 0.8 ⁇ m to 5.5 ⁇ m.
• the temperature range of homogenization is effective to set the temperature range of homogenization to 500°C or higher and lower than 560°C, and the time to 3 hours or higher and lower than 5 hours.
• This homogenization can reduce the variation in the concentration of Si contained in the ⁇ phase that crystallizes during the solidification process, and by growing fine Si phases to soften the wire, it is possible to control the deformation behavior of the Si phase due to the subsequent wiredrawing process.
• the diameter of the Si phase can then be controlled by repeating wiredrawing and intermediate heat treatment. When wiredrawing is performed, the Si phase deforms in the direction of the central axis of the wire, and some of the Si phase breaks and becomes finer. On the other hand, when intermediate heat treatment is performed, the Si phase grows.
• R2 represents the diameter of the wire before processing (mm)
• R1 represents the diameter of the wire after processing (mm).
• the final heat treatment is performed without performing the intermediate heat treatment, it is not possible to simultaneously obtain the necessary fracture elongation and the desired diameter of the Si phase for the Al alloy bonding wire. Therefore, it is effective to set the conditions of the intermediate heat treatment to focus on controlling the diameter of the Si phase and the final heat treatment to focus on controlling the fracture elongation, as described above.
• the intermediate heat treatment under specified conditions and growing the Si phase in advance, it is possible to easily control the Si phase to the desired diameter after the final heat treatment. This allows the wire to be recrystallized to ensure the necessary breaking elongation for Al alloy bonding wire, while the Si phase can be grown and easily controlled to the desired diameter.
• the intermediate and final heat treatments can be carried out by heating for a certain period of time in an electric furnace. It is preferable that the atmosphere during heat treatment be an inert or reducing atmosphere to prevent excessive oxidation of Al and Si.
• wiredrawing process 1 The wiredrawing process from the ingot obtained by melting to the first intermediate heat treatment is called “wiredrawing process 1".
• the wiredrawing process from the first intermediate heat treatment to the second intermediate heat treatment is called “wiredrawing process 2".
• the wiredrawing process from the second intermediate heat treatment to the final wire diameter is called “wiredrawing process 3". It is effective to set the wire feed speed in wiredrawing process 1 to 15 m/min or more and less than 25 m/min, the wire feed speed in wiredrawing process 2 to 30 m/min or more and less than 55 m/min, and the wire feed speed in wiredrawing process 3 to 70 m/min or more and less than 90 m/min.
• the die angle In order to control the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section of the wire to a range of 30% or more and 80% or less, it is effective to control the reduction angle of the die (hereinafter also referred to as the "die angle"). In order to control the orientation ratio of the crystal orientation ⁇ 110> of the Si phase in the L cross section to a range of 30-80%, it is effective to set the die angle to 14° or more and less than 18°. This is thought to be because when the wire enters the die, the contact area between the wire and the die changes, changing the compressive stress applied to the wire surface, allowing the crystal orientation of the Si phase to be controlled to the desired range.
• Electrode device By using the wire of the present invention to connect electrodes on a semiconductor chip to external electrodes on a lead frame or substrate, a semiconductor device can be manufactured.
• the semiconductor device of the present invention includes a circuit board, a semiconductor chip, and a bonding wire for electrically connecting the circuit board and the semiconductor chip, the bonding wire being the wire of the present invention.
• the circuit board and semiconductor chip are not particularly limited, and any known circuit board and semiconductor chip that can be used to configure a semiconductor device may be used.
• a lead frame may be used instead of a circuit board.
• the semiconductor device may be configured to include a lead frame and a semiconductor chip mounted on the lead frame, as in the semiconductor device described in JP 2020-150116 A.
• Semiconductor devices include various semiconductor devices used in electrical products (e.g., computers, mobile phones, digital cameras, televisions, air conditioners, solar power generation systems, etc.) and vehicles (e.g., motorcycles, automobiles, trains, ships, aircraft, etc.), among which power semiconductor devices are preferred.
• electrical products e.g., computers, mobile phones, digital cameras, televisions, air conditioners, solar power generation systems, etc.
• vehicles e.g., motorcycles, automobiles, trains, ships, aircraft, etc.
• the method of preparing the samples will be described.
• the raw material Al had a purity of 4N (99.99% by mass or more), with the remainder consisting of inevitable impurities.
• the alloying elements Si, Ni, Pd, and Pt had a purity of 99.99% by mass or more, with the remainder consisting of inevitable impurities.
• the Al alloy used for the bonding wire was produced by loading the Al raw material and the raw material of the alloying elements into an alumina crucible and melting them using a high-frequency heating furnace.
• the atmosphere in the furnace during melting was an Ar atmosphere, and the maximum temperature of the molten metal during melting was 800 ° C.
• the cooling method after melting was furnace cooling.
• a cylindrical ingot with a diameter of 6 mm was obtained by melting, and the ingot was subjected to homogenization treatment, followed by wire drawing using a die and intermediate heat treatment to produce a wire with a diameter of 300 ⁇ m.
• the temperature range of the homogenization treatment was 500°C or higher and lower than 560°C, and the time was 3 hours or higher and lower than 5 hours.
• a commercially available lubricant was used during the wire drawing process, and the wire area reduction rate per die during the wire drawing process was 10.5% or higher and lower than 12.5%.
• the temperature range of the intermediate heat treatment was 400°C or higher and lower than 440°C, and the time of the intermediate heat treatment was 1 hour or higher and lower than 2 hours.
• the intermediate heat treatment was performed twice, with the wire diameter for the first intermediate heat treatment being 2.6 to 3.0 times the final wire diameter, and the wire diameter for the second intermediate heat treatment being 1.6 to 2.0 times the final wire diameter.
• the temperature range of the final heat treatment was 250°C or higher and lower than 360°C, and the time of the final heat treatment was 20 hours or higher and lower than 24 hours.
• the wire feed speed in wire drawing process 1 was 15 m/min or more and less than 25 m/min
• the wire feed speed in wire drawing process 2 was 30 m/min or more and less than 55 m/min
• the wire feed speed in wire drawing process 3 was 70 m/min or more and less than 90 m/min.
• additional heat treatment was performed before the final heat treatment at the final wire diameter, and the additional heat treatment conditions were a temperature range of 540°C or more and less than 560°C, and a time period of 1.5 seconds or more and less than 3.0 seconds.
• the wire drawing was performed using a die with a die angle of 14° or more and less than 18°.
• the concentration analysis of the elements contained in the bonding wire was measured using an ICP-OES ("PS3520UVDDII” manufactured by Hitachi High-Tech Science Co., Ltd.) or an ICP-MS ("Agilent 7700x ICP-MS” manufactured by Agilent Technologies, Inc.) as an analytical device.
• ICP-OES PS3520UVDDII
• ICP-MS Alent 7700x ICP-MS
• the L cross section of the Al alloy bonding wire was used as the inspection surface, and the average diameter and shape of the Si phase were measured.
• the wire central axis and the cross section in the wire central axis direction including the wire central axis (L cross section) are as shown in FIG. 1.
• FE-SEM and EDS were used for the measurement, and the average diameter of the Si phase, the length of the Si phase in the wire central axis direction (a), and the length in the direction perpendicular to the wire central axis (b) were calculated using the above-mentioned procedure.
• the measurement area was determined to be 200 ⁇ m in the wire central axis direction, and the entire wire was included in the direction perpendicular to the wire central axis.
• the cross section When processing the cross section to expose the L cross section of the Al alloy bonding wire, it may be shifted from the wire central axis.
• the length of the L cross section in the direction perpendicular to the wire central axis is 90% or more of the wire diameter, it can be considered as a cross section including the wire central axis. This is because if the length of the L cross section in the perpendicular direction is 90% or more, the effect of the shift from the wire central axis on the measurement results of the average diameter of the Si phase and the shape of the Si phase is negligibly small.
• the L-section of the Al alloy bonding wire was used as the inspection surface, and the orientation ratio of the crystal orientation ⁇ 110>, which has an angle difference of 15° or less with respect to the wire central axis direction, was measured among the crystal orientations of the Si phase in the wire central axis direction.
• a method was used that combines information on the Si concentration obtained by SEM-EDS and information on the crystal orientation obtained by EBSD. In detail, the concentration measurement of Al and Si using EDS and the crystal orientation analysis using EBSD were performed simultaneously.
• the orientation ratio of the crystal orientation ⁇ 110> was calculated by using the analysis software attached to the device. Three measurement regions were randomly selected at intervals of 1 m or more in the wire central axis direction, and the arithmetic average value of the orientation ratios of the crystal orientation ⁇ 110> of the Si phase obtained from the three measurement regions was taken as the orientation ratio of the crystal orientation ⁇ 110> of the Si phase of the measurement sample.
• the measurement area was determined to be 200 ⁇ m in the direction of the central axis of the wire, and the entire wire was included in the direction perpendicular to the central axis of the wire.
• the L-section of the wire of the Al alloy bonding wire was used as the inspection surface, and the concentration measurement of Al and Si using EDS and the crystal orientation analysis using EBSD were performed simultaneously.
• the analysis software attached to the device was used to determine that it was a grain boundary if the orientation difference between the measurement points was 15° or more, and the circle equivalent diameter was calculated.
• the arithmetic mean value of the circle equivalent diameter of each ⁇ phase was taken as the average diameter of the ⁇ phase.
• the measurement area was 200 ⁇ m in the direction of the wire central axis, and the entire wire was included in the direction perpendicular to the wire central axis.
• the evaluation method of the Al alloy bonding wire will be described.
• the wire diameter of the Al alloy bonding wire used for the evaluation was ⁇ 300 ⁇ m.
• the semiconductor chip used was made of Si, and the electrodes on the semiconductor chip were made of an alloy with a composition of Al-0.5% Cu, which was formed to a thickness of 5 ⁇ m.
• the substrate used was an Al alloy with a Ni film formed to a thickness of 15 ⁇ m.
• a commercially available wire bonder (manufactured by Ultrasonic Industries Co., Ltd.) was used to bond the Al alloy bonding wire.
• a commercially available thermal shock tester was used to evaluate the temperature cycle test.
• the sample chamber was moved between a low temperature chamber and a high temperature chamber to repeatedly raise and lower the temperature.
• the temperature of the low temperature chamber was set to -40°C
• the temperature of the high temperature chamber was set to 175°C.
• the test started with the sample chamber in the high temperature chamber, and the test was performed from the time the sample chamber moved to the low temperature chamber to the time it returned to the high temperature chamber, which was defined as one cycle.
• the time the sample chamber stayed in the low temperature chamber and the high temperature chamber was set to 20 minutes, respectively.
• the sample to be subjected to the temperature cycle test had a structure in which a semiconductor chip was mounted on a substrate, and the electrodes on the semiconductor chip and the electrodes on the substrate were connected with Al alloy bonding wires. After the start of the test, the sample was taken out every 100 cycles, and a shear test was performed on the first joint. The arithmetic average value of the shear strength of the first joints at five randomly selected locations was used as the value of the shear strength of the first joints used to evaluate the temperature cycle reliability. The number of cycles at which the shear strength dropped to 70% or less of the value before the temperature cycle test was taken as the joint life.
• a commercially available high-speed thermal shock tester was used for the evaluation of the high-speed temperature cycle test.
• the samples used for the high-speed temperature cycle test were the same as those used for the evaluation of temperature cycle reliability.
• Thermal loads were repeatedly applied to the samples placed in the sample chamber of the high-speed thermal shock tester, with heating and cooling being one cycle.
• the minimum temperature was -50°C, and the maximum temperature was 175°C.
• the arithmetic average value of the shear strengths of the first joints at five randomly selected locations was used as the value of the shear strength of the first joints used for the evaluation of temperature cycle reliability.
• the number of cycles at which the shear strength dropped to 70% or less of the value before the temperature cycle test was taken as the joint life.
• the evaluation method of the 1st bondability will be described.
• the 1st bondability was evaluated by a shear strength test.
• the 1st bond was performed at 10 places under general bonding conditions, and the shear strength of the 1st bond was measured.
• a commercially available micro shear strength tester was used to measure the shear strength.
• the shear rate was 200 ⁇ m/sec, and the height of the shear tool was 10 ⁇ m from the electrode surface.
• the shear strength was measured by fixing the substrate to which the wire was bonded with a jig.
• the observation field was 99% or more of the wire diameter, and the length in the wire central axis direction was 1 mm or more.
• the area to check for corrosion was the entire observation field.
• the surfaces of the 10 wires were observed at a magnification of 200 times. If corrosion was observed at a position 15 ⁇ m from the surface of the wire toward the wire central axis, it was judged to be problematic in practical use and rated as "0". If corrosion was not observed at a position 15 ⁇ m from the surface of the wire toward the wire central axis of all 10 wires, it was judged to be problemless in practical use and rated as "1".
• All of the bonding wires of Examples 1 to 80 contain 3.0 mass% or more and 10.0 mass% or less of Si, and the average diameter of the Si phase in the L cross section is 0.8 ⁇ m or more and 5.5 ⁇ m or less. It was confirmed that they exhibit excellent temperature cycle reliability and good 1st bondability.
• the average value of the ratio (a / b) of the length (a) of the Si phase in the L cross section in the wire central axis direction to the length (b) in the direction perpendicular to the wire central axis is 1.3 to 3.2. It was confirmed that the bonding wires of Example Nos.
• the bonding wires of Examples 35 to 48, 61 to 64, and 77 to 80 in which the orientation ratio of the crystal orientation ⁇ 110> was 30% or more and 80% or less, exhibited better results in terms of loop straightness. Furthermore, it was confirmed that the bonding wires of Examples 17 to 22 and 43 to 48 containing at least one of Ni, Pd, and Pt in a total amount of 3 ppm by mass to 150 ppm by mass exhibited better corrosion resistance in a high-temperature and high-humidity environment.
• the bonding wires of Comparative Examples 1 to 6 had at least one of the Si concentration and the average diameter of the Si phase in the L cross section outside the range of the present invention, and either the temperature cycle reliability or the 1st bondability was not sufficiently obtained.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Wire Bonding (AREA)
• Conductive Materials (AREA)
• Die Bonding (AREA)
• Manufacturing & Machinery (AREA)

Priority Applications (30)

Applications Claiming Priority (2)

Publications (1)

Family

ID=91379118

Family Applications (8)

Family Applications After (7)

Country Status (8)

Families Citing this family (3)

Citations (10)

Family Cites Families (10)

• 2023
  • 2023-06-30 DE DE112023005086.4T patent/DE112023005086T5/de active Pending
  • 2023-06-30 KR KR1020257021796A patent/KR20250114537A/ko active Pending
  • 2023-06-30 JP JP2023579485A patent/JP7518305B1/ja active Active
  • 2023-06-30 EP EP23900220.7A patent/EP4534709A4/en active Pending
  • 2023-06-30 WO PCT/JP2023/024324 patent/WO2024122089A1/ja not_active Ceased
  • 2023-06-30 US US18/874,698 patent/US20250379177A1/en active Pending
  • 2023-06-30 CN CN202380020896.7A patent/CN118660981A/zh active Pending
  • 2023-11-27 WO PCT/JP2023/042366 patent/WO2024122380A1/ja not_active Ceased
  • 2023-11-27 KR KR1020257021989A patent/KR20250116123A/ko active Pending
  • 2023-11-27 EP EP23900500.2A patent/EP4632092A1/en active Pending
  • 2023-11-27 WO PCT/JP2023/042369 patent/WO2024122381A1/ja not_active Ceased
  • 2023-11-27 EP EP23900498.9A patent/EP4632090A1/en active Pending
  • 2023-11-27 CN CN202380083564.3A patent/CN120303422A/zh active Pending
  • 2023-11-27 EP EP23900499.7A patent/EP4632091A1/en active Pending
  • 2023-11-27 JP JP2024536442A patent/JP7833550B2/ja active Active
  • 2023-11-27 CN CN202380083554.XA patent/CN120435577A/zh active Pending
  • 2023-11-27 KR KR1020257021779A patent/KR20250114535A/ko active Pending
  • 2023-11-27 JP JP2024536441A patent/JP7626906B2/ja active Active
  • 2023-11-27 JP JP2024536440A patent/JP7626905B2/ja active Active
  • 2023-11-27 WO PCT/JP2023/042373 patent/WO2024122383A1/ja not_active Ceased
  • 2023-11-27 KR KR1020257021793A patent/KR20250114536A/ko active Pending
  • 2023-11-27 WO PCT/JP2023/042371 patent/WO2024122382A1/ja not_active Ceased
  • 2023-11-27 WO PCT/JP2023/042374 patent/WO2024122384A1/ja not_active Ceased
  • 2023-11-27 CN CN202380083569.6A patent/CN120303423A/zh active Pending
  • 2023-12-01 TW TW112146769A patent/TW202432852A/zh unknown
  • 2023-12-01 TW TW112146772A patent/TW202503076A/zh unknown
  • 2023-12-01 TW TW112146768A patent/TW202430658A/zh unknown
  • 2023-12-01 TW TW112146773A patent/TW202432853A/zh unknown
• 2024
  • 2024-06-04 WO PCT/JP2024/020313 patent/WO2025115257A1/ja active Pending
  • 2024-06-04 WO PCT/JP2024/020314 patent/WO2025115258A1/ja active Pending
  • 2024-07-04 JP JP2024107900A patent/JP2024138348A/ja active Pending
• 2025
  • 2025-04-16 JP JP2025067311A patent/JP2025108597A/ja active Pending

Patent Citations (10)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events