WO2006132410A1 - Silver alloy for electrode, wiring and electromagnetic shielding - Google Patents

Abstract

Disclosed is a silver alloy for electrodes, wiring and electromagnetic shielding which is mainly composed of silver while containing at least one element selected from aluminum, indium, tin, bismuth, gallium, zinc, strontium, calcium, germanium, magnesium, antimony, lithium and phosphorus as first additional elements. Gallium, indium, tin and zinc are preferable as the first additional elements, and it is further preferable to add at least one element selected from palladium, dysprosium and copper as second additional elements. The total concentration of these additional elements is preferably 0.01-20.0 atom%.

Description

 Specification

 Silver alloy for electrode, wiring and electromagnetic shielding

 Technical field

 [0001] The present invention relates to a silver alloy useful as an electrode and wiring material, and further as an electromagnetic wave shielding material, and relates to a silver alloy having significantly improved environmental resistance and a low specific resistance value.

 Background art

 [0002] Silver is a metal material that has the lowest specific resistance among metals and is excellent in electrical conductivity, and can be expected to be applicable as an electrode material or a wiring material. In particular, application as a solar cell electrode material, a display device such as an organic light emitting display or a liquid crystal display, a thin film electrode material of various electronic components, and a wiring material is being studied. This is because refractory metal materials such as tantalum, chromium, molybdenum, and titanium that have been used as wiring materials in the past have a relatively high electrical resistance value and therefore signal delay has become a problem. It is. Patent Document 1: Japanese Patent Laid-Open No. 10-48650

 Patent Document 2: Japanese Patent Laid-Open No. 2003-328184

 [0003] In recent years, with the spread of electronic devices such as notebook computers and word processors, the necessity of shielding electromagnetic waves has been highlighted in view of the effects of electromagnetic noise generated by these electronic devices on each other and on the human body. ing. Silver is a material that can be expected as a constituent material for electromagnetic wave shields because of its low specific resistance. This is because attenuation (absorption) when electromagnetic waves pass through an object depends on the frequency of the electromagnetic waves and the specific resistance of the object, but there is a tendency for attenuation to increase as the specific resistance decreases.

 Patent Document 3: JP-A-6-164186

 Patent Document 4: Japanese Patent Laid-Open No. 11 97885

 Patent Document 5: Japanese Patent Laid-Open No. 2003-152389

[0004] Further, the low specific resistance leads to the fact that a film as thin as possible can be formed while suppressing the resistance value. Therefore, silver is also useful for forming a light-transmitting film having electrical conductivity (having an electromagnetic wave shielding effect). In the above electrode / wiring material and electromagnetic wave shielding material, transparent electrodes such as transparent electrodes and glass are used. As a material to give an electromagnetic wave shielding effect to the body I can expect.

 Disclosure of the invention

 Problems to be solved by the invention

 [0005] On the other hand, there is a problem that silver is easily corroded because of poor environmental resistance. The change in silver due to corrosion is a force that is marked by the appearance of blackening. At the same time, the resistivity increases and the transmittance deteriorates. The cause of this silver corrosion is basically due to moisture and heat in the environment of use, although the details differ depending on the application. And the problem of characteristic deterioration due to such corrosion of silver affects the reliability of the apparatus.

 Means for solving the problem

 [0006] Accordingly, an object of the present invention is to provide a material suitable as an electrode wiring material and an electromagnetic wave shielding material while greatly improving the environmental resistance and maintaining a low specific resistance. In the present invention, the environmental resistance refers to the property of suppressing the specific resistance and transmittance due to the influence of the environment in which the silver alloy is placed, such as a heating atmosphere, a humidified atmosphere, and a sulfurized atmosphere. Sometimes referred to as heat resistance, moisture resistance, and sulfidation resistance.

 [0007] The inventors of the present invention, who should solve the above problems, have selected a suitable additive element for improving the environmental resistance while mainly using silver. As a result, additive elements such as aluminum, indium, tin, bismuth, gallium, zinc, strontium, calcium, germanium, magnesium, antimony, lithium, and phosphorus, which have lower melting points than silver, are added as additive elements. The inventors have found that there is an effect of improving the environmental performance, and have come up with the present invention.

 That is, the present invention is mainly composed of silver, and at least aluminum, indium, tin, bismuth, gallium, zinc, strontium, calcium, germanium, magnesium, antimony, lithium, and phosphorus as the first additive element group. It is a silver alloy for electrode, wiring, and electromagnetic wave shielding that contains one kind.

According to the study by the present inventors, among the low melting point elements listed as the first additive element group, in a silver alloy containing gallium, indium, tin, zinc, magnesium and aluminum, reflection / transmission It has been confirmed that the moisture resistance required for the membrane is maintained at a particularly high level. By selecting these elements singly or by selecting 2 elements, 3 elements or more elements from the group and using them in combination as the `` first additive element group '', Moisture resistance can be improved. In addition, the first additive element other than gallium, indium, tin, zinc, magnesium, and aluminum is also effective in improving moisture resistance.

 In the present invention, the second additive element group includes platinum, gold, rhodium, iridium, ruthenium, palladium, lead, copper, manganese, silicon, nickel, chromium, connort, yttrium, iron, scandium, zirconium. , Titanium, Niobium, Molybdenum, Tantalum, Tandastene, Hafnium, Lanthanum, Cerium, Prasium, Neodium, Samarium, Palladium, Gadolinium, Terbium, Dysprosium, Holmium, Thulium, Ytterbium, Boron, Erbium, Carbon These are preferably further added. These elements work together with the first additive element group to further improve the environmental resistance.

 [0011] In particular, a silver alloy to which palladium, dysprosium, copper, titanium, zirconium, manganese, gadolinium, erbium, prasedium, samarium, lanthanum, and yttrium are added as the second additive element group is in a heating environment. It is a preferable alloy because it can effectively suppress the aggregation phenomenon occurring in the thin film material.

 [0012] The second additive element group component is added mainly for the purpose of improving the heat resistance of the alloy. That is, these elements that should ensure the heat resistance required for the thin film are added alone, or two elements, three elements, or more multi-elements are selected and added.

[0013] Here, the concentration of the additive element group, 0. 01-20. 0 preferably the atoms _^0/0. This is because if the amount added is less than 0.01 atomic percent, the effect of improving the environmental resistance is not achieved, and if the concentration of the added element exceeds 20.0 atomic percent, the specific resistance of the alloy increases. Here, there are actually a variety of products using the thin film having a silver alloy strength according to the present invention, and there are various required characteristic specifications. In this respect, the present invention basically has a high transmittance and a low specific resistance, but there are many products that require a thin film having a maximum environmental resistance. In such a case, the maximum value of the additive element concentration is 20.0 atomic%. On the other hand, the concentration of additive elements when improving the transmittance and specific resistance while emphasizing environmental resistance performance is 10.0 atomic% or less. Furthermore, when the highest priority is given to transmittance and specific resistance, the concentration of the additive element is 5.0 atomic percent or less. In this way, the type and amount of additive element can be adjusted in consideration of the required specifications for each product to which the thin film is applied.

[0014] The above-described silver alloy as the reflecting / transmitting film material according to the present invention is produced by a melting and forging method, It can be manufactured by the ligation method. There is no particular difficulty in the production by the melting and forging method, and it can be produced by a general method in which each raw material is weighed, melted and mixed to produce it. In addition, in the production by the sintering method, it is possible to produce by a general method in which each raw material is weighed and sintered.

 The silver alloy according to the present invention is suitable as various electrical and electronic devices, electrode materials for components, and wiring materials. The silver alloy according to the present invention also has good light transmittance by adjusting the film thickness appropriately. Therefore, it is also useful as a wiring material for transparent electrodes such as ITO. When applied to the use of these electrode materials and wiring materials, the film thickness is preferably 40 to 1500A. This is to ensure fine workability while considering reliability and durability. Also, in this film thickness range, 40 to 150 A is preferable when the wiring material is used for a transparent electrode that places importance on transmittance, but 1000 to 1200 for electrodes and wiring that do not place importance on transmittance. To do that.

 [0016] The silver alloy according to the present invention is also suitable as a constituent material of an electromagnetic wave shielding body. When the present invention is applied to an electromagnetic wave shielding body, an electromagnetic wave shielding body can be obtained by vapor-depositing or joining a silver alloy according to the present invention on an appropriate support surface. As the support, plate-like, sheet-like rubber and fiber can be applied. Further, the silver alloy according to the present invention can be thinned while maintaining the electromagnetic wave attenuation capability, and can have good transmittance, so that it has light transmittance with glass as a support. It can be a shielding material. In plasma displays, a coating for shielding electromagnetic waves may be applied to the light emitting surface. However, the present invention, which has excellent light transmission, can also be applied to powerful applications.

[0017] The form of the silver alloy in the electromagnetic wave shielding application may be any of a thin film, a plate material, a net, and a powder, but a thin film is preferred. Its film thickness is 400-150A, especially 50-120

A is preferable. While maintaining the electromagnetic shielding effect by ensuring conductivity, the transmittance

This is to make it 80% or more.

[0018] Then, when forming a thin film made of the silver alloy according to the present invention for the above application, a sputtering method can be applied. Therefore, the sputtering target having the silver alloy force according to the present invention can produce electrodes, wirings, and electromagnetic wave shielding materials made of an alloy film having desirable characteristics. The invention's effect

 [0019] As described above, the silver alloy according to the present invention has remarkably improved environmental resistance compared to pure silver, and can maintain characteristics such as transmittance and specific resistance even during long-term use. . The present invention is useful as an electromagnetic shielding material in addition to an electrode material and a wiring material. The silver alloy according to the present invention has good adhesion in a thin film state, and is suitable for the above-mentioned use from this viewpoint.

 BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described together with comparative examples. Here, silver alloys having various compositions ranging from binary to quinary with silver as the main component were produced, and targets were produced from these to form thin films by sputtering. The thin film was subjected to corrosion tests (acceleration tests) under various environments, and changes in properties after the corrosion tests were examined. Note that the alloy according to the present invention is not limited to the binary to quinary alloys targeted by the present embodiment, but may be a multi-element alloy having more than that. Depending on the product specifications, multi-component alloys with 6 or more elements can be manufactured. In its manufacture, there are no particular problems and mass production is possible.

 In the production of a silver alloy, each metal is weighed to a predetermined concentration, melted in a high-frequency melting furnace, and mixed to obtain an alloy. Then, this was put into a mold and solidified to form an ingot, which was forged, rolled, and heat treated, and then molded into a sputtering target. Target production by powder sintering is also possible.

[0022] The thin film was manufactured by placing a slide glass substrate (borosilicate glass) and a target in a sputtering apparatus, ^{evacuating the} apparatus to 5.0 X 10 ^_3 Pa, and then ^adding argon gas to 5. OX 10 ^_1 Introduced up to Pa. As sputtering conditions, a film was formed at a direct current of 0.4 kW for 8 seconds, and the film thickness was 120 A. The film thickness distribution was within ± 10%.

 [0023] The evaluation of the properties of the manufactured thin film was conducted by conducting a corrosion test in which the thin film was exposed to various environments and evaluating the properties of the thin film before and after the test. In the present embodiment, for the various silver alloy thin films that were produced, a composition test focusing on environmental resistance performance and a composition testing focusing on transmittance and specific resistance were performed.

[0024] A: Composition with emphasis on environmental resistance A salt drop test and an adhesion test were performed as tests for compositions that place importance on environmental resistance. As for the practicality of products with silver alloy thin films, priority is given to ensuring durability in human living environments. That is, a product having a silver thin film needs to be maintained without deterioration in performance even if there is a corrosive factor such as a person touching it directly or a food or food adhering. The salt water drop test and adhesion test conducted this time take into consideration such a use environment.

 [0025] The salt water drop test is intended to perform a deterioration acceleration test on the assumption of adhesion of seasonings such as human sweat, soy sauce, and miso. 10. Prepare a 0% NaCl aqueous solution (25 ° C), drop 2 or 3 drops onto the 120A silver alloy film immediately after film formation on a slide glass, and observe the change to judge the durability performance. . The evaluation was made by the following 0-5 grade evaluation.

 "5": Torayo · · · No peeling

 "4": Good · · 'Some peeling

 "3": Normal-· Half peel off

 “1” • .fftt, • • Some remaining

 "0" '· ·

 [0026] A test for evaluating the adhesion of the thin film to the substrate was conducted for the salt water drop test with a rating of 3 or more. The adhesion test was performed on three types of samples after exposure to the following environment using thin film samples (film thickness 120 A) on glass slides of each composition.

 (1) Sample immediately after film formation

 (2) Sample after heating test after film formation, heated on air at 250 ° C for 1 hour on hot plate

(3) Sample after humidification test after film formation and exposed to an atmosphere of 100 ° C and 100% humidity for 24 hours

 [0027] For each sample, 11 mm score lines were placed on the thin film on the substrate using a metal mask special tool with a cutter niff at lmm pitch and cross-cut. (Vertical and horizontal 10 × 10) was formed. A commercially available cellophane tape was affixed so as to cover the cross-cut portion, and after sufficiently pressing and adhering, it was peeled off at right angles to the surface. After peeling off the tape, the number of remaining squares was counted and evaluated in five stages.

“5”: Best, no peeling "4": good part peeling

 “3”: normal, half peeled

 "1": Evil part remaining

 "0": Worst '' '

 [0028] Table 1 shows the evaluation results of the salt water drop test and the adhesion test. For comparison, the table also shows the pure silver thin film and the test results.

[0029] [Table la]

O-one OZAV

] 0?

lc]

 Sample composition Salt water drop test Adhesion test

 Immediately after film formation After heating test I After humidification test

121 Ag-1.2Ga-0.2E (-0.2Ce 5 5 5 5

122 AE-1.2Ga-0.2Er-0.2Ho 4 5 5 4

123 Ag-1.2Ga-0.2Pr-0.2Nd 5 5 4 5

124 AE-1.2Ga-0.2Pr-0.2Yb 5 5 5 5

125 Ag-1.2Ga-0.2Pi-0.2Tb 5 5 4 5

126 Ag-1.2Ga-0.2Pi ~ 0.2Ce 5 5 5 5

127 Ag-1.2Ga-0.2Pr-0.2Ho 4 5 5 4

128 Ag-1.0Ga-1.7Cu-0.1 Dy 5 5 5 5

129 Ag-1.OGa-1.7Cu-0.1 Gd 5 5 5 5

130 AE-1 -OGa-1.7Cu-0.1Er 5 5 5 5

131 Ag-1. OGa-1.7Cu-0.1Pr 5 5 5 5

132 Ag-1 OGa-1.7CU-0.1 5 5 5 5

133 Ag-1. OGa-1.7Cu-0.1Y 5 5 4 5

134 Ag-1.OGa-1, 7Cu-0.1 Sin 5 5 5 4

135 Ag-1.OGa-1.7Cu-0.1 Nd 5 5 5 4

136 Ag-1.0Ga-1.7Cu-0.1Yb 5 5 5 5

137 Ag-1.0Ga-1.7Cu-0.1Tb 5 5 4 5

138 Ag-1. OGa-1.7Cu-0.1Ce 5 5 5 5

139 Ag-1.0Ga-1.7Cu-0.1 Ho 5 5 4 4

140 Ag-1.0Ga-1.7Cu-0.1So 4 5 5 4

141 Ag-1. OGa-1.7Cu-0.1Eu 4 5 5 4

142 Ag-1.OGa-1 JCu-0.1 Tm 4 5 4 5

143 Ag-1.OGa-1.7Cu-0.1 Dy-0.1Pd 5 5 5 5

144 AB-1.OGa-1.7Cu-0.1 Gd-0.1 Pd 5 5 5 5

145 Ag-1.OGa-1.7CU-0.1 Er-0.1 Pd 5 5 5 5

146 Ag-1.OGa-1.7Cu-0.1 Pr-0.1 Pd 5 5 5 5

147 Ag-1.OGa-1.7Cu-0.1 La-0.1 Pd 5 5 5 5

148 Ag-1.OGa-1 JCu-0.1 Y-0.1 Pd 4 5 4 4

149 Ag-1 OGa-1 JCu-O.I Sm-0.1 Pd 4 5 5 4

150 Ag-1.OGa-1.7CU-0.1 Gd-0.1 Er 5 5 5 5

151 Ag-1.OGa-1.7Cu-D 1 Gd-0.1 Pr 5 5 5 5

152 Ag-1 OGa-1 7Cu-0.1 Er-0.1 Pr 5 5 5 5

153 Ag-1.OGa-1.7CU-0.1 Gd-0.1 Dy 4 5 5 5

154 Ag-1.OGa-1 JCu-0.1 Gd-0.1 Sm 5 5 5 4

155 Ag-1.OGa-1.7Cu-0.1 Gd-0.1 La 5 5 5 5

156 Ag-1.OGa-1 JCu-O.I Gd-0.1 Y 5 5 4 5

157 Ag-1.OGa-1.7Cu-0.1 Er-0.1 Dy 5 5 5 5

158 Ag-1.QGa-1.7Cu-0.1 Er-0.1 Sm 4 5 5 5

159 Ag-1 OGa-1 7Cu-0.1 Er-0.1 La 5 5 5 5

160 Ag-1.OGa-1.7Cu-0.1 Er-0.1 Y 5 5 5 4

161 Ag-1.OGa-1 JCu-0.1 Pr-0.1 Dy 5 5 5 5

162 Ag-1.OGa-1.7Cu-0.1 Pr-0.1 Sm 5 5 4 5

163 Ag-1.OGa-1.7Cu-0.1 Pi-0.1La 5 5 5 5

164 Ag-1.0Ga-1.7Cu-0.1 Pr-0.1Y 5 5 5 4

165 Ag-1.2Ga-1.7Cu-0.1 Er-0.1 d 5 5 4 5

166 Ag-1.2Ga-1 7Cu-0.1 Er-0.1 Yb 5 5 5 5

167 Ag-1.2Ga-1 7CU-0.1 Ei ~ 0.1Tb 5 5 4 4

168 Ag-1.2Ga-1.7CU-0.1 Er-0.1 Ce 5 5 5 5

169 Ag-1.2Ga-1 JCu-0.1 Er ^ O.1 Ho 5 5 5 4

170 Ag-1.2Ga-1.7CU-0.1 Pr-0.1 Nd 5 5 4 5

171 Ag-1.2Ga-1 JCu-0.1 Pr-0.1 Yb 5 5 5 5

172 Ag-1.2Ga-1.7Cu-0.1 Pr-0.1 Tb 5 5 5 4

173 Ag-1.2Ga-1.7Cu-0.1 Pr-0.1 Ce 5 5 5 5

174 Ag-1.2Ga-1 JCu-O.I Pr-0.1 Ho 5 5 5 4

175 Ag-1.OGa-1.OSn-0.1 Dy-0.1 Pd 5 5 5 5

176 Ag-1.OGa-1.OSn-0.1 Gd-0.1 Pd 5 5 5 5

177 Ag- 1.OGa-1.OSn-0.1 Et ^ O.1 Pd 5 5 5 5

178 Ag-1.OGa-1 OSn-0.1 Pr-0.1 Pd 5 5 4 4

179 Ag-1 OGa-1 OSn-0.1 La-0.1 Pd 5 5 5 5

180 AE-1.OGa-1.0Sn-0.1Y-0.1 Pd 4 5 5 4

Ae 0 I 3 0 0 [0032] From these test results, it was confirmed that the silver alloy thin film produced in the present embodiment was excellent in durability against salt water, better adhesion than pure silver thin film, and had high environmental resistance. It was done. This environmental resistance improves as the concentration of the additive element increases.

 [0033] B: Composition with emphasis on the eddy rate and resistivity

 Next, a silver alloy having a composition giving priority to transmittance and specific resistance was evaluated. In this evaluation as well, a thin film sample (film thickness 120A) deposited on a slide glass was placed on a hot plate, heated in air at 250 ° C for 1 hour, and the characteristics after heating were evaluated (heating test) ). In addition, as a humidification test to examine the moisture resistance of the thin film, the thin film was exposed to an atmosphere at a temperature of 100 ° C and a humidity of 100%, and the characteristics after humidification were evaluated. In the humidification test, the exposure time was 24 hours.

 [0034] The properties evaluated before and after the corrosion test are transmittance and specific resistance. The transmittance was measured by a spectrophotometer, a thin film was formed, and the transmittance of each thin film was evaluated relative to the transmittance of the substrate (borosilicate glass) as 100.

 [0035] First, Table 2 shows the evaluation results of the transmittance before and after the corrosion test. Each measured value is a value at wavelengths of 400 η m, 550 nm, and 650 nm (corresponding to blue, yellow, and red wavelengths in the visible light region). The table also shows the test results for thin films manufactured from targets that also have pure silver power for comparison.

[0036] [Table 2]

400nm 550nm 650nm Sample composition

 Heating immediately after deposition 6 Humidity test Heating test immediately after deposition Humidification test Heating test immediately after deposition

Ag-3.9AI 82.5 72.4 76.2 64.5 54.3 57.7 56.2 45.8 49.3

Ag-0.9In 81.9 72.0 77.2 66.7 56.4 61.3 56.4 46.1 51.0

Ag-0.9Sn 76.9 85.8 77.7 61.6 70.2 61.8 51.5 59.9 51.4

Ag-1.4Sr 76.8 86.3 77.5 60.7 70.0 60.8 51.4 60.3 51.3

Ag-2.6Ca 86.9 76.0 77.3 69.4 57.9 58.7 60.4 49.4 50.3

Ag-0.3Ga 75.8 79.6 75.9 62.5 65.9 61.7 53.5 56.7 52.7

Ag-0.5Ga 79.7 86.1 81.2 61.2 67.3 62.2 53.5 59.5 54.2

Ag-0.8Ga 81.8 82.9 82.6 66.0 66.6 66.1 56.6 56.9 56.9

Ag-1.5Ga 81.9 82.3 82.5 66.0 66.6 66.7 56.Θ 57.5 57.3

Ag-2.0Ga 82.1 83.4 82.9 68.9 69.7 68.9 59.1 60.5 59.7

Ag-0.5AI-0.5In 85.9 76.2 77.5 70.0 59.9 60.7 60.4 50.2 51.2

Ag-0.5In-0.4Sm 85.7 76.1 77.3 70.5 60.5 61.4 60.0 50.2 51.1

Ag-0.5In-O.8Cu 86.2 76.5 77.9 68.2 58.4 59.1 59.7 49.9 51.1

Ag-0.5In-0.5Bi 77.8 86.0 76.3 60.6 68.2 58.4 53.3 60.9 50.7

Ag-0.5In-0.5Ge 77.0 86.7 77.9 63.6 73.0 63.6 54.5 63.8 54.6

Ag-0.5Sn-0.4Cu 77.2 86.0 77.3 62.2 70.3 61.0 52.9 61.2 52.0

Ag-0.8Ga-0.52n 86.0 75.3 78.0 68.7 57.6 60.0 61.2 50.2 52.3

Ag-0.2Ga-0.2Cu 75.3 79.1 75.4 59.4 62.8 58.6 49.3 53.1 49.1

Ag-0.5Ga-0.3Cu 76.2 78.9 75.1 60.8 63.2 59.3 51.7 54.1 50.1

Ag-1.0Ga-0.5Cu 81.5 81.8 82.1 66.3 66.2 66.5 56.1 55.9 56.0

Ag-0.25Ga-0.25Sn 86.2 76.5 77.9 73.2 62.8 64.0 64.1 53.6 54.4

Ag-0.5Ga-0.5Sn 77.6 87.0 76.8 60.0 68.9 58.4 51.9 60.4 50.3

Ag ~ 0.2Ga-0.3Pd 79.0 85.2 80.4 61.8 67.4 62.8 54.3 60.5 55.3

Ag-0.5Ga-0.5Pd 79.3 85.7 80.8 65.3 71.4 66.1 55.9 61.8 56.6

Ag-1.0Ga-0.5Pd 80.1 86.5 81.7 62.6 68.4 63.4 53.9 59.9 54.7

Ag-0.5Ga-0.5In 86.2 75.8 77.6 72.2 61.5 62.9 62.7 51.9 53.3

Ag-0.2Ga-0.2ln 78.0 86.3 76.7 64.2 72.0 62.1 55.5 62.4 52.4

Ag-1.2Ga-0.2In 86.2 76.4 77.0 70.9 60.8 61.0 61.9 51.6 51.8

Ag-0.6Ga-0.2In 77.1 86.β 76.4 59.6 68.5 58.1 50.8 60.0 49.4

Ag 76.5 69.8 66.5 58.7 52.2 50.8 48.4 42.9 42.2

[0037] In the evaluation of the transmittance, regarding the thin film having the silver alloy strength according to the present invention, when the rate of change immediately after the film formation and after the corrosion test are compared, all are lower than the rate of change in the case of pure silver. It was confirmed that the silver alloy was superior to pure silver at each wavelength. Overall, the power that increases the transmittance in the short wavelength range. The difference between the transmittance at the short wavelength of 400 nm and the transmittance at the long wavelength of 650 nm shows that silver is a large 28% in the case of pure silver. In the case of an alloy, it is smaller than this value. In this way, the difference in transmittance reduction with wavelength is low! This is a great advantage when trying to obtain white light as transmitted light.

 [0038] Next, Table 3 shows the evaluation results of the specific resistance of each silver alloy thin film before and after the corrosion test.

[0039] [Table 3] Specific gravity (UQ cm) Material composition

 Immediately after film formation After heating test After humidification test

Ag-3.9AI 4.655 4.869 4.846

Ag-0.9In 4.803 4.998 4.981

Ag-0.9Sn 8.448 8.811 8.777

Ag-1.4Sr 3.895 4.156 4.136

Ag-2.6Ca 5.072 5.493 5.381

Ag-0.3Ga 2.673 2.895 2.863

Ag-0.5Ga 3.559 3.741 3.755

Ag-0.8Ga 3.670 3.776 3.754

Ag-1.5Ga 5.634 5.775 5.752

Ag-2.0Ga 6.344 6.477 6.503

Ag-0.5AI-0.5In 4.856 5.109 5.075

Ag-0.5In-0.4Sm 4.189 4.428 4.407

Ag-0.5In-0.8Cu 4.970 5.199 5.174

Ag-0.5In-0.5Bi 4.354 4.537 4.511

Ag-0.5In-0.5Ge 4.664 4.998 4.972

Ag-0.5Sn-0.4Cu 4.363 4.642 4.612

Ag-0.8Ga-0.5Zn 4.692 4.889 4.861

Ag-0.2Ga-0.2Cu 3.203 3.254 3.261

Ag-0.5Ga-0.3Cu 3.945 3.992 4.004

Ag-1.0Ga-0.5Cu 5.227 5.253 5.248

Ag-0.25Ga-0.25Sn 3.799 3.955 3.940

Ag-0.5Ga-0.5Sn 5.076 5.264 5.238

Ag-0.2Ga-0.3Pd 3.599 3.682 3.671

Ag-0.5Ga-0.5Pd 4.677 4.761 4.738

Ag-1.0Ga-0.5Pd 4.856 4.914 4.905

Ag-0.5Ga-0.5In 4.827 5.001 4.981

Ag-0.2Ga-0.2In 4.065 4.276 4.289

Ag-1.2Ga-0.2In 5.428 5.596 5.569

Ag-0.6Ga-0.2In 4.274 4.454 4.424

Ag 2.521 3.252 3.126 In the resistivity evaluation, the resistivity of pure silver before the corrosion test was the lowest, but increased by 29% after the heating test and increased by 24% after the humidification test. In contrast to this In the case of the silver alloy according to Ming, the rate of increase in the specific resistance is within 0.5% to 8.3%. These results are consistent with the fact that in the case of a silver alloy, the transmittance is not easily changed by an environmental test, indicating that it is electrically stable.

 [0041] Next, an adhesion test was performed on the thin film before and after the corrosion test. In this test, similar to the adhesion test described above, the thin film was cross-cut to form 100 squares of 1 mm square. Then, cellophane tape was affixed and brought into close contact and peeled off at once. The evaluation method was evaluated in five stages as described above. Table 4 shows the results of this adhesion test.

[0042] [Table 4]

 As a result, in the case of a pure silver thin film, it can be seen that the entire surface of the thin film peels off after the corrosion test. On the other hand, in the case of the silver alloy according to the present invention, the adhesiveness is greatly improved, and in particular, it is possible to obtain a strong adhesive force that does not peel off at all as well as immediately after film formation after the environmental test. This is very effective for practical purposes of creating electrodes and wiring patterns.

[0044] In this embodiment, the etching properties of each thin film were also evaluated. Again, above A thin film before and after the corrosion test was used as a sample. Photoresist was applied to the thin film on the substrate with a spin coater, dried, and a special pattern (100 m line and space) was exposed with a photomask, held for a certain period of time, then developed and dried. Then, the thin film was etched for about 30 seconds in the silver etching solution (adjusted appropriately depending on the type of additive element because of the difference in etching rate). After that, the resist was peeled off, washed, and dried, and the substrate was completed. This substrate was observed using an optical microscope and an electron microscope of 100 to 400 times. A substrate with a resist was used to measure the amount of overetching and taper, and the cross section was observed and measured after cutting. The evaluation was made on a five-point scale based on each item. The “0” and “1” judgments were unsuitable for practical use, and the “4” and “5” judgments were judged to be recommended for practical use. The evaluation results are shown in Table 5.

[Table 5]

εϊ / -π // ε900ί1: 2 ^ 0 / ϊ3εϊ900ΟΖΑν

[0046] From the evaluation results, in the case of a pure silver thin film, the linearity was good and the amount of residue after etching was small, but the amount of over-etching in the cross-sectional pattern was large, and the resulting taper was not suitable for practical use. there were. On the other hand, in the case of the silver alloy thin film according to the present invention, it is greatly improved by the effect of various additive elements and has reached a practical level.

 Industrial applicability

[0047] The present invention is useful as an electrode wiring material for various display devices such as a thin film transistor type liquid crystal display (TFT-LCD), an organic EL display, and a plasma display.

 [0048] A TFT-LCD has a structure in which a liquid crystal material is sealed between two glass substrates. A filter is formed on the upper glass substrate, and a thin transistor (TFT) is formed on the lower glass substrate. The A gate electrode, a source electrode, and a drain electrode are formed on the TFT substrate side electrode. O The silver alloy according to the present invention is useful as a wiring material for these electrode materials and ITO transparent electrodes. For example, an insulating film or the like is formed on a transparent substrate of borosilicate glass, and Ag—O. 5% Ga-0.3% 01 is formed with a film thickness of 120 as an example of the silver alloy thin film according to the present invention. When the resistivity was evaluated by etching, the resistivity was as low as 3.945 μΩ 'cm, and it was confirmed to have excellent environmental resistance and its usefulness.

 [0049] An organic EL display is a display that utilizes the electoluminescence phenomenon, and the EL element itself emits light. In general, the glass substrate ZITO transparent electrode Z first dielectric layer Z phosphor layer Z second dielectric layer Z The back electrode phosphor is sandwiched between a pair of dielectrics. The silver alloy according to the present invention is effective as a wiring material for the electrode material and the ITO transparent conductive film. For example, an ITO transparent conductive film is formed on a transparent substrate of borosilicate glass, and then Ag-O. 2% Ga-0.2% Cu is formed with a film thickness of 120A as an example of a silver alloy thin film according to the present invention. When the resistivity was evaluated as a wiring material after etching, the resistivity was as low as 3.203 μΩ 'cm, and it was confirmed to have excellent environmental resistance and its usefulness.

[0050] In general, a plasma display has a structure in which a data electrode and a display electrode (scanning Z sustaining electrode) are mounted in parallel in a glass substrate, and a neon-based gas is sealed in the gap. Then, the neon-dominated gas sealed in each pixel is turned into plasma by voltage and released. Electricity is emitted to emit ultraviolet rays from the gas, and this is emitted to the red, blue and green phosphors coated on the inside of the glass substrate. The silver alloy according to the present invention is effective as an electrode for various electrodes. For example, a protective film, a dielectric layer, etc. are formed on a transparent substrate of borosilicate glass, and Ag—O. 2% Ga-0. 3% Pd is used as an electrode material as an example of a silver alloy thin film according to the present invention. As a result, it was confirmed that the resistivity was 3.599 Ω'cm, which was low, and it was excellent in environmental resistance.

 The silver alloy which concerns on this invention is suitable also as a constituent material of an electromagnetic wave shielding body. When applied to an electromagnetic wave shielding body, an electromagnetic wave shielding body can be obtained by depositing or bonding a silver alloy according to the present invention on an appropriate support surface. As the support, plate-like acrylic polycarbonate, sheet-like rubber, or fiber can be applied. Moreover, it can be set as the light-transmitting shielding material using glass as a support. Therefore, even if a coating for shielding electromagnetic waves is applied to the light emitting surface of the plasma display panel, high reliability can be obtained because there is no deterioration in image quality due to high light transmittance. For example, a transparent dielectric layer and an Ag—O. 5% Ga thin film (thickness 12 OA) as a practical example of the silver alloy thin film according to the present invention were formed on a transparent substrate of borosilicate glass and evaluated as a multilayer structure. In this case, the specific resistance is 3.559 Ω'cm, which is a low specific resistance. This transparent dielectric layer had good adhesion to the silver alloy thin film, and high transmittance exceeding 50% was obtained over all wavelengths.

Claims

The scope of the claims

 [I] Containing silver as a main component and containing at least one kind of aluminum, indium, tin, bismuth, gallium, zinc, strontium, calcium, germanium, magnesium, antimony, lithium, and phosphorus as a first additive element group A silver alloy for shielding electrodes, wiring and electromagnetic waves.

2. The silver alloy according to claim 1, wherein the first additive element group is gallium, indium, tin, zinc, magnesium, and aluminum.

[3] Furthermore, as a second additive element group, platinum, gold, rhodium, iridium, ruthenium, palladium, lead, copper, manganese, silicon, nickel, chromium, connort, yttrium, iron, scandium, zirconium, Add at least one of titanium, niobium, molybdenum, tantalum, tungsten, hafnium, lanthanum, cerium, prasedium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, thulium, ytterbium, boron, erbium, and carbon The silver alloy according to claim 1 or 2.

[4] The silver alloy according to claim 3, wherein the second additive element group is at least one of palladium, dysprosium, copper, titanium, zirconium, manganone, gadolinium, erbium, prasedium, samarium, lanthanum, and yttrium. .

[5] The silver alloy according to any one of claims 1 to 4, wherein the total strength of the additive element concentration is 0.01 to 20.0 at%.

6. The silver alloy according to claim 5, wherein the total concentration of the additive elements is 0.01 to: LO. 0 atomic%.

[7] An electronic component comprising the electrode or wiring made of the silver alloy according to any one of [1] to [6].

 [8] A display device comprising the electrode or wiring comprising the silver alloy cover according to any one of claims 1 to 6.

 [9] An electromagnetic wave shielding body comprising the silver alloy thin film according to any one of claims 1 to 6 and a support that supports the thin film.

[10] A liquid crystal display comprising the thin film of the silver alloy according to any one of [1] to [6].

[II] An EL display comprising the thin film having a silver alloy strength according to any one of claims 1 to 6.

[12] A plasma display comprising the thin film of the silver alloy strength according to any one of [1] to [6].

 [13] An SED display comprising the thin film having the silver alloy strength according to any one of claims 1 to 6.

 [14] An antireflection film comprising the thin film having the silver alloy strength according to any one of [1] to [6].

 [15] The silver alloy force target according to any one of claims 1 to 6.