Surface acoustic wave device and electronic component

A surface acoustic wave device utilizing surface acoustic waves including a leaky surface acoustic wave (LSAW) having a frequency equal to or higher than 2 GHz, the surface acoustic wave comprising:

• a piezoelectric substrate, configured such that a surface acoustic wave propagates along an X-axis direction on a lithium tantalate substrate cut perpendicularly to a Y-axis rotated by 45° to 46° around a crystal X-axis;
• an IDT electrode, including:
• a pair of busbars, each of which extends along a propagation direction of a surface acoustic wave, and is made of a conductor film formed over the piezoelectric substrate in parallel with each other, and
• electrode fingers, made of a conductive film and arranged to intersect each other in a comb-tooth shape from one of the busbars to the opposite busbar;
• and
• a reflector, having:
• a pair of reflector busbars, formed over the piezoelectric substrate in parallel with each other, each of which is provided in one side and the other side of the IDT electrode in a propagation direction of a surface acoustic wave and extends along a propagation direction of a surface acoustic wave, and
• reflector electrode fingers, formed to connect the reflector busbars to each other,
• wherein, a thickness of the conductor film in each of the electrode fingers is set to 7.5% λ to 8% λ, where λ denotes a periodic length of the electrode fingers, and a metallization ratio expressed as a value obtained by dividing a width D of the electrode finger by a sum of the width D of the electrode finger and an interval S between the neighboring electrode fingers is set to 0.55 to 0.65.