Wavelength tunable interference filter, method for manufacturing wavelength tunable interference filter, optical module, and electronic apparatus

A method for manufacturing a wavelength tunable interference filter, the method comprising:

• a first substrate formation step of forming a first reflection film that reflects part of incident light and transmits another part thereof, a first electrode, and a wiring portion on a first substrate;
• a second substrate formation step of forming a second reflection film that reflects part of incident light and transmits another part thereof and a second electrode on a second substrate;
• a third substrate formation step of forming a third substrate having a top surface portion and a sidewall portion having a frame shape in a plan view;
• a gap formation step of disposing the first substrate and the second substrate so that the first reflection film and the second reflection film face each other and the first electrode and the second electrode face each other;
• and
• a bonding step of bonding the first substrate and the third substrate to each other,
• wherein the bonding step includes disposing the first substrate and the third substrate so that the second substrate is located in a space surrounded by the top surface portion, the sidewall portion, and the first substrate and the wiring portion extends continuously from inside the space to outside the space and bonding an end surface of the sidewall portion that faces the first substrate to the first substrate to hermetically seal the space.

An optical module comprising:

• a first substrate;
• a second substrate facing the first substrate;
• a first reflection film provided on the first substrate, the first reflection film reflecting part of incident light and transmitting another part thereof;
• a second reflection film provided on the second substrate so as to face the first reflection film, the second reflection film reflecting part of incident light and transmitting another part thereof;
• a gap changing section that changes a dimension of a gap between the first reflection film and the second reflection film;
• a wiring portion connected to the gap changing section;
• a third substrate having a top surface portion and a sidewall portion extending from the top surface portion toward the first substrate and having a frame shape in a plan view;
• and
• a detector that detects light of a wavelength selected based on interference of light that enters the gap between the first reflection film and the second reflection film,
• wherein an end surface of the sidewall portion of the third substrate that faces the first substrate is bonded to the first substrate so that a space surrounded by the top surface portion of the third substrate, the sidewall portion of the third substrate, and the first substrate is hermetically sealed,
• the second substrate and the gap changing section are disposed in the space, and
• the wiring portion is disposed on the first substrate and continuously extends from inside the space to outside the space.

An electronic apparatus comprising:

• a wavelength tunable interference filter including a first substrate, a second substrate facing the first substrate, a first reflection film provided on the first substrate, the first reflection film reflecting part of incident light and transmitting another part thereof, a second reflection film provided on the second substrate so as to face the first reflection film, the second reflection film reflecting part of incident light and transmitting another part thereof, a gap changing section that changes a dimension of a gap between the first reflection film and the second reflection film, a wiring portion connected to the gap changing section, and a third substrate having a top surface portion and a sidewall portion extending from the top surface portion toward the first substrate and having a frame shape in a plan view;
• and
• a control unit that controls the wavelength tunable interference filter,
• wherein an end surface of the sidewall portion of the third substrate that faces the first substrate is bonded to the first substrate so that a space surrounded by the top surface portion of the third substrate, the sidewall portion of the third substrate, and the first substrate is hermetically sealed,
• the second substrate and the gap changing section are disposed in the space, and
• the wiring portion is disposed on the first substrate and continuously extends from inside the space to outside the space.