Resonator Device

A resonator device comprising:

• a piezoelectric substrate;
• an excitation electrode formed at the piezoelectric substrate;
• an extension electrode formed at the piezoelectric substrate and extending from the excitation electrode;
• a case in which the piezoelectric substrate is accommodated;
• a coupling electrode formed in the case;
• and
• a conductive adhesive bonding the extension electrode and the coupling electrode, wherein
• the case has a bottom surface and an inner wall protruding from the bottom surface and surrounding the bottom surface in a frame shape,
• when the bottom surface is viewed in a plan view, a region of the bottom surface surrounded by the inner wall is a quadrilateral, and the coupling electrode is located at a corner of the quadrilateral,
• the inner wall includes a first inner wall and a second inner wall coupled to each other at the corner,
• the piezoelectric substrate has a first surface facing the bottom surface, a second surface opposite to the first surface, and a side surface coupling the first surface and the second surface,
• the side surface has a first side surface facing the first inner wall and a second side surface facing the second inner wall,
• the extension electrode faces the coupling electrode at the first surface and extends from the first surface to the first side surface and the second side surface,
• a portion of the extension electrode that overlaps the first side surface is a first side surface electrode, and a portion of the extension electrode that overlaps the second side surface is a second side surface electrode, and
• the conductive adhesive reaches the first side surface electrode and the second side surface electrode from the coupling electrode, bonds the first side surface electrode and the first inner wall, and bonds the second side surface electrode and the second inner wall.