Elastic wave device

1. An elastic wave device comprising:

a LiNbO 3 substrate;

an IDT electrode disposed on the LiNbO 3 substrate; and

an aluminum nitride film disposed on the LiNbO 3 substrate to cover the IDT electrode such that the elastic wave device utilizes a leaky elastic wave that propagates on the LiNbO 3 substrate; wherein

the IDT electrode is composed of a metal including, as a main component, one material selected from a group consisting of Cu, Al, Au, Pt, and Ni;

Euler angles of the LiNbO 3 substrate are (0°±5°, θ, 0°±5°);

when X denotes a wavelength-normalized thickness of the IDT electrode and Y denotes θ of the Euler angles, Y is in any of ranges in Table 1 to Table 5 depending on a kind of the metal of which the IDT electrode is composed and a range of a wavelength-normalized thickness of the aluminum nitride film:

TABLE 1

Cu electrode

 0.02 ≤ <0.075

Y = 119.8 − 1644X + 64107X 2 −

820434X 3 + 4.5 × 10 6 X 4 − 1.2 × 10 7 X 5 +

1.1X 6 to Y = 153 + 169X − 363X 2

0.075 ≤ <0.125

Y = 106.7 − 1278X + 53014X 2 − 700901X 3 +

4.1 × 10 6 X 4 − 1.1 × 10 7 X 5 + 1.1 × 10 7 X 6 to Y =

143 + 209X − 739X 2 + 907X 3

0.125 ≤ <0.175

Y = 89.6 − 493X + 25919X 2 − 255926X 3 +

911653X 4 − 1.1X 5 to Y = 132 + 207X − 195X 2

0.175 ≤ <0.225

Y = 79.4 − 207.6X + 21115X 2 − 220752X 3 +

803734X 4 − 988585X 5 to Y = 124 +

547X − 2351X 2 + 3513X 3

0.225 ≤ <0.275

Y = 70.4 − 35.7X + 13366X 2 − 125408X 3 +

392064X 4 − 406193X 5 to Y = 125.8 + 547.4X −

2351X 2 + 3513X 3

TABLE 2

Al electrode

 0.02 ≤ <0.075

Y = 154 − 17X − 18 to Y = 154 − 17X + 18

0.075 ≤ <0.125

Y = 132 − 13X − 18 to Y = 132 − 13X + 18

0.125 ≤ <0.175

Y = 116 − 13X − 18 to Y = 116 − 13X + 18

0.175 ≤ <0.225

Y = 101 − 13X − 18 to Y = 101 − 13X + 18

0.225 ≤ <0.275

Y = 88 − 13X − 18 to Y = 88 − 13X + 18

TABLE 3

Au electrode

 0.02 ≤ <0.075

Y = 143.1 − 2591X + 221241X 2 − 6.66109 ×

10 6 X 3 + 7.5 × 10 7 X 4 − 2.9 × 10 8 X 5 to Y = 154 +

513X − 2508X 2

0.075 ≤ <0.125

Y = 113.3 − 1613X + 173621X 2 − 5.4 ×

10 6 X 3 + 6.1 × 10 7 X 4 − 2.4 × 10 8 X 5 to Y = 151 +

187X + 1187X 2

0.125 ≤ <0.175

Y = 91.57 − 1590X + 203628X 2 − 5.7 ×

10 6 X 3 + 5.8 × 10 7 X 4 − 2.1 × 10 8 X 5 to Y = 140 +

265X + 623X 2

0.175 ≤ <0.225

Y = 103.7 − 559.1X + 42955X 2 −

704717X 3 + 3 × 10 6 X 4 to Y = 146 + 191X − 215X 2

0.225 ≤ <0.275

Y = 88.8 + 26.8X + 66840X 2 − 4.45 × 10 6 X 3 +

1.15 × 10 8 X 4 − 1.25 × 10 9 X 5 + 4.8 × 10 9 X 6 to

Y = 176 − 450X + 2317X 2

TABLE 4

Pt electrode

 0.02 ≤ <0.075

Y = 134 + 303X + 2874X 2 − 445059X 3 +

3X 4 to Y = 159 + 333X − 1040X 2

0.075 ≤ <0.125

Y = 101 − 345X + 66704X 2 − 1.4 × 10 6 X 3 +

7.6 × 10 6 X 4 to Y = 147 + 350X + 281X 2

0.125 ≤ <0.175

Y = 94.45 − 2780X + 313312X 2 − 9.1 × 10 6 X 3 + 10 ×

10 7 X 4 − 3.8 × 10 8 X 5 to Y = 140 + 258X + 918X 2

0.175 ≤ <0.225

Y = 101.1 + 1132X − 94867X 2 + 3.4 × 10 6 X 3 − 4.8 ×

10 7 X 4 + 2.2 × 10 8 X 5 to Y = 154 − 66X + 1563X 2

0.225 ≤ <0.275

Y = 91.1 − 793.7X + 132135X 2 − 6.4 × 10 6 X 3 + 1.4 ×

10 8 X 4 − 1.4 × 10 9 X 5 + 5.1 × 10 9 X 6 to Y =

175 − 527X + 4617X 2 − 13850X 3

TABLE 5

Ni electrode

 0.02 ≤ <0.075

Y = 115.9 − 1162X + 47603X2 − 584771X 3 + 3.1 ×

10 6 X 4 − 7.4 × 10 6 X 5 + 6.7 × 10 6 X 6 to Y = 154 +

51X + 19.5X 2

0.075 ≤ <0.125

Y = 100.3 − 769X + 30871X 2 − 326052X 3 + 1.3 ×

10 6 X 4 − 1.7 × 10 6 X 5 to Y = 134 + 154X − 300X 2

0.125 ≤ <0.175

Y = 67.99 + 1440X − 46900X 2 + 917682X 3 −

9.1 × 10 6 X 4 + 4.5 × 10 7 X 5 − 1.1 × 10 8 X 6 + 1.1 ×

10 8 X 7 to Y = 139 + 194X − 177X 2

0.175 ≤ <0.225

Y = 68.79 + 618.4X − 15149X 2 + 215569X 3 −

1.35 × 10 6 X 4 + 3.64 × 10 6 X 5 − 3.51 × 10 6 X 6 to Y =

129 + 642X − 3232X 2 + 5479X 3

0.225 ≤ <0.275

Y = 59.867 + 826.5X − 15571X 2 + 176484X 3 −

985113X 4 + 2.5 × 10 6 X 5 − 2.3 × 10 6 X 6 to Y = 118 +

576X − 2604X 2 + 4075X 3 .

2. An elastic wave device comprising:

a LiNbO 3 substrate;

an IDT electrode disposed on the LiNbO 3 substrate; and

a silicon nitride film disposed on the LiNbO 3 substrate to cover the IDT electrode such that the elastic wave device utilizes a leaky elastic wave that propagates on the LiNbO 3 substrate; wherein

the IDT electrode is composed of a metal including, as a main component, one material selected from a group consisting of Cu, Al, Au, Pt, and Ni;

Euler angles of the LiNbO 3 substrate are (0°±5°, θ, 0°±5°);

when X denotes a wavelength-normalized thickness of the IDT electrode and Y denotes θ of the Euler angles, Y is in any of ranges in Table 6 to Table 10 depending on a kind of the metal of which the IDT electrode is composed and a range of a wavelength-normalized thickness of the silicon nitride film:

TABLE 6

Cu electrode

 0.02 ≤ <0.075

Y = 111 − 498X + 41204X 2 − 506285X 3 + 2.1 × 10 6 X 4 − 2.9X 5 to Y = 150 + 376X − 1867X 2 + 3151X 3

0.075 ≤ <0.125

Y = 96.3 − 854X + 42082X 2 − 459289X 3 + 1.86 × 10 6 X 4 − 2.55 × 10 6 X 5 to Y = 135 + 333X − 868X 2 + 621X 3

0.125 ≤ <0.175

Y = 58.42 + 3058X − 122626X 2 + 2.55 × 10 6 X 3 − 2.61 × 10 7 X 4 + 1.35 × 10 8 X 5 − 3.43 × 10 8 X 6 + 3.38 × 10 8 X 7 to Y =

125 + 322X − 568X 2

0.175 ≤ <0.225

Y = 69.36 + 1741X − 69965X 2 + 1.51 × 10 6 X 3 − 1.56 × 10 7 X 4 + 8.037 × 10 7 X 5 − 2.01 × 10 8 X 6 + 1.95 × 10 8 X 7 to Y =

126 + 263X − 424X 2

0.225 ≤ <0.275

Y = 76.57 − 46.58X + 10865X 2 − 95112X 3 + 272166X 4 − 249810X 5 to Y = 121 + 263X − 424X 2

TABLE 7

Al electrode

 0.02 ≤ <0.075

Y = 106 − 124X − 204X 2 to Y = 163 − 105X + 714X 2 − 1122X 3

0.075 ≤ <0.125

Y = 92 + 98X − 72X 2 to Y = 153 − 88X + 423X 2

0.125 ≤ <0.175

Y = 85 + 188X − 409X 2 to Y = 144 + 76X − 235X 2

0.175 ≤ <0.225

Y = 80 + 197X − 433X 2 to Y = 141 + 67X − 188X 2

0.225 ≤ <0.275

Y = 76.7 + 133.1X − 239X 2 to Y = 136 + 53X − 134X 2

TABLE 8

Au electrode

 0.02 ≤ <0.075

Y = 138.8 − 521.5X + 59626X 2 − 1.6 × 10 6 X 3 + 9.7 × 10 6 X 4 to Y = 154.6 + 323X − 1005X 2

0.075 ≤ <0.125

Y = 78.95 − 2244X + 308668X 2 − 9.23 × 10 6 X 3 + 1.03 × 10 8 X 4 − 3.92 × 10 8 X 5 to Y = 121.5 + 1406X − 8286X 2

0.125 ≤ <0.175

Y = 75.14 − 972X + 163196X 2 − 4.73 × 10 6 X 3 + 5.02 × 10 7 X 4 − 1.83X 5 to Y = 150.8 + 103.8X + 1446.4X 2

0.175 ≤ <0.225

Y = 95.46 − 381X + 38962X 2 − 766242X 3 + 3.89 × 10 6 X 4 to Y = 139.1 + 191.4X − 215.1X 2

0.225 ≤ <0.275

Y = 90.23 − 363.8X + 15154X 2 − 181875X 3 − 8.63 × 10 6 X 4 + 5.45 × 10 7 X 5 to Y = 118.5 + 1461.9X − 8600.4X 2

TABLE 9

Pt electrode

 0.02 ≤ <0.075

Y = 137.8 + 1045.9X − 35270X 2 + 182370X 3 to Y = 178.8 − 459.9X + 2654.2X 2

0.075 ≤ <0.125

Y = 85.3 + 1563.5X − 13505X 2 − 334251X 3 + 2.9 × 10 6 X 4 to Y = 126.2 + 841.4X + 3530.7X 2 − 64451X 3

0.125 ≤ <0.175

Y = 80.25 + 1737.6X − 29616X 2 + 116182X 3 to Y = 134.1 + 233X + 1288X 2

0.175 ≤ <0.225

Y = 102 − 2120X + 171560X 2 − 4.29 × 10 6 X 3 + 4.1 × 10 7 X 4 − 1.35 × 10 8 X 5 to Y = 143.8 + 106.3X + 681.3X 2

0.225 ≤ <0.275

Y = 85.45 + 2448X − 171170X 2 + 4.82 × 10 6 X 3 − 5.56 × 10 7 X 4 + 2.19 × 10 8 X 5 to Y = 172.2 − 496.4X + 3216X 2

TABLE 10

Ni electrode

 0.02 ≤ <0.075

Y = 77.39 + 889X − 10413X 2 + 39192X 3 − 48758X 4 to Y = 133.7 + 570.1X − 2561X 2 + 39863587X 3

0.075 ≤ <0.125

Y = 96.1 − 265.4X + 17881X 2 − 193077X 3 + 724808X 4 − 910916X 5 to Y = 143.1 + 148X − 216.8X 2

0.125 ≤ <0.175

Y = 83.26 − 139X + 17433X 2 − 212387X 3 + 874177X 4 − 1.2 × 10 6 X 5 to Y = 143.7 + 208.6X − 275.3X 2

0.175 ≤ <0.225

Y = 72.04 − 196.1X + 23821X 2 − 258686X 3 + 977904X 4 − 1.2 × 10 6 X 5 to Y = 126.2 + 498.9X − 1958X 2 + 2608X 3

0.225 ≤ <0.275

Y = 69.12 − 307.4X + 22905X 2 to Y = 120.9 + 428.9X − 1427X 2 + 1528X 3

3. The elastic wave device according to claim 1 , wherein an attenuation constant is about 0.2 or less.

4. The elastic wave device according to claim 2 , wherein an attenuation constant is about 0.2 or less.