Patent ID: 7489064

Claim:
A boundary acoustic wave device comprising: a quartz substrate; an IDT located on the quartz substrate; and a dielectric arranged on the quartz substrate so as to cover the IDT; wherein a boundary acoustic wave propagates across a boundary between the quartz substrate and the dielectric; a thickness of the IDT is determined so that the velocity of the boundary acoustic wave is below those of a slow transverse wave propagating across the quartz substrate and a slow transverse wave propagating across the dielectric; and θ and ψ of Euler angles (0°, θ, ψ) of the quartz substrate are in any one of regions surrounded by points A01 to A16, B01 to B16, C01 to C16, D01 to D13, E01 to E17, F01 to F11, G01 to G23, and H01 to H14 in the Tables 1 to 8: TABLE 1 θ[°] ψ[°] A01 100 146 A02 110 144 A03 120 144 A04 130 145 A05 136 147 A06 140 151 A07 140 156 A08 135 163 A09 130 166 A10 125 168 A11 120 168 A12 112 168 A13 110 166 A14 98 155 A15 97 150 A16 100 146 TABLE 2 θ[°] ψ[°] B01 83 100 B02 86 95 B03 92 93 B04 100 92 B05 150 86 B06 180 81 B07 180 110 B08 151 126 B09 140 128 B10 130 129 B11 120 129 B12 105 127 B13 95 122 B14 85 110 B15 83 105 B16 83 100 TABLE 3 θ[°] ψ[°] C01 104 60 C02 109 55 C03 118 52 C04 131 52 C05 146 54 C06 152 56 C07 161 60 C08 165 65 C09 160 70 C10 150 72 C11 140 73 C12 130 73 C13 120 72 C14 114 71 C15 105 66 C16 104 60 TABLE 4 θ[°] ψ[°] D01 95 31 D02 100 36 D03 180 50 D04 180 19 D05 150 12 D06 140 11 D07 130 10 D08 120 10 D09 111 12 D10 106 14 D11 102 18 D12 98 23 D13 95 31 TABLE 5 θ[°] ψ[°] E01 0 170 E02 15 175 E03 20 176 E04 75 177 E05 80 176 E06 85 175 E07 88 173 E08 87 168 E09 80 161 E10 70 154 E11 60 149 E12 50 144 E13 35 142 E14 18 140 E15 10 140 E16 0 141 E17 0 170 TABLE 6 θ[°] ψ[°] F01 23 121 F02 27 125 F03 45 128 F04 50 128 F05 55 125 F06 55 122 F07 50 116 F08 45 113 F09 35 113 F10 30 115 F11 23 121 TABLE 7 θ[°] ψ[°] G01 0 111 G02 10 105 G03 20 100 G04 30 95 G05 40 93 G06 55 92 G07 65 90 G08 70 88 G09 71 83 G10 70 72 G11 65 55 G12 55 51 G13 33 50 G14 25 40 G15 0 21 G16 0 51 G17 17 54 G18 20 56 G19 23 60 G20 18 70 G21 10 77 G22 0 82 G23 0 111 TABLE 8 θ[°] ψ[°] H01 22 11 H02 23 17 H03 33 25 H04 45 30 H05 52 31 H06 60 30 H07 69 26 H08 73 21 H09 72 15 H10 66 11 H11 46 6 H12 33 6 H13 26 8 H14 22 11.