Multilayer substrate, actuator, and method of manufacturing multilayer substrate

A multilayer substrate comprising:

• a stacked body including a principal surface and provided by stacking a plurality of insulating base material layers made of a thermoplastic resin;
• and
• a coil including:
• a plurality of coil conductors provided on the plurality of insulating base material layers;
• and
• a winding axis extending in a stacking direction in which the plurality of insulating base material layers are stacked;
• wherein
• the plurality of coil conductors include:
• a first coil conductor that is closest to the principal surface;
• and
• a second coil conductor adjacent to or in a vicinity of the first coil conductor and including a wide portion of which a line width is larger than a line width of the first coil conductor;
• the wide portion includes:
• an overlapping portion that overlaps with the first coil conductor when viewed from the stacking direction;
• and
• a non-overlapping portion that does not overlap with the first coil conductor when viewed from the stacking direction, and is adjacent to the overlapping portion in a width direction that is perpendicular or substantially perpendicular to an extension direction of the second coil conductor;
• the non-overlapping portion is curved to be closer to the principal surface than to the overlapping portion;
• and
• when viewed from the stacking direction, the non-overlapping portion is located on at least one of an outer peripheral side and an inner peripheral side of the second coil conductor in the width direction, at the wide portion.