Surface acoustic wave device and manufacturing method therefor

A surface acoustic wave device comprising:

• a piezoelectric substrate including a main surface;
• a conductor pattern located on the main surface and including a surface acoustic wave element pattern, a pad and a feed line that is electrically connected to the pad and extends up to an outer peripheral edge of the main surface;
• a support layer including a frame that is located on the main surface and has a frame-shaped structure that extends along the outer peripheral edge of the main surface and so that a gap is provided between the frame and the outer peripheral edge, and a pad adjacent portion that is located on the pad;
• a cover that is bonded to the support layer and faces the main surface;
• and
• a through conductor that is electrically connected to the pad and is located inside a through hole that penetrates through the pad adjacent portion of the support layer in a direction in which the main surface is viewed in plan;
• wherein
• a closed space is provided and surrounded by the piezoelectric substrate, the cover and the support layer;
• the feed line includes a separated feed line that intersects a separated portion of the frame that is separated from the pad adjacent portion;
• and
• the support layer further includes a reinforcement portion that is located on the main surface and intersects the separated feed line close to the separated portion.