A sensor for detecting a temperature distribution imparted on a substrate in an environment is disclosed. The sensor includes a sensor substrate with one or more temperature sensing elements formed on the sensor substrate. In embodiments, a temperature sensing element includes at least one cavity with a thermally expandable material disposed within the cavity and a channel extending from the cavity with a slug disposed within the channel. In embodiments, the cavity has a fixed volume and is enclosed by a cover layer disposed or formed over the cavity. The thermally expandable material is configured to extend from the cavity into the channel to actuate the slug from a first position within the channel to at least a second position within the channel, where the position of the slug is indicative of a temperature of a respective portion of the sensor substrate.

A high-resolution temperature sensor based on an external sac and a fixed wavelength includes an external sac, a metal block, two waveguides, two metal films and a signal light; the external sac is connected with the first waveguide, the metal block is disposed in the first waveguide, and is movable; the first waveguide is connected with a second waveguide; and the signal light has a fixed wavelength.

A high-resolution temperature sensor based on an external sac and a fixed wavelength includes an external sac, a metal block, two waveguides, two metal films and a signal light; the external sac is connected with the first waveguide, the metal block is disposed in the first waveguide, and is movable; the first waveguide is connected with a second waveguide; and the signal light has a fixed wavelength.

A high-resolution temperature sensor based on a built-in sac and a spectral valley-point-method includes a built-in sac, a metal block, two waveguides, two metal films and a signal light; the built-in sac is connected with a first waveguide; the metal block is disposed in the first waveguide, and is movable; the first waveguide is connected with a second waveguide; and the signal light is broadband light or the frequency-sweeping light.

A high-resolution temperature sensor based on a built-in sac and a spectral valley-point-method includes a built-in sac, a metal block, two waveguides, two metal films and a signal light; the built-in sac is connected with a first waveguide; the metal block is disposed in the first waveguide, and is movable; the first waveguide is connected with a second waveguide; and the signal light is broadband light or the frequency-sweeping light.

A sensor for detecting a temperature distribution imparted on a substrate in an environment is disclosed. The sensor includes a sensor substrate with one or more temperature sensing elements formed on the sensor substrate. In embodiments, a temperature sensing element includes at least one cavity with a thermally expandable material disposed within the cavity and a channel extending from the cavity with a slug disposed within the channel. In embodiments, the cavity has a fixed volume and is enclosed by a cover layer disposed or formed over the cavity. The thermally expandable material is configured to extend from the cavity into the channel to actuate the slug from a first position within the channel to at least a second position within the channel, where the position of the slug is indicative of a temperature of a respective portion of the sensor substrate.