Method and apparatus for nanoscale infrared absorption tomography

A system for nanoscale tomographic infrared absorption imaging, the system comprising:

• an infrared light emitter;
• an actuated probe configured to detect displacement of a surface of a sample;
• and
• a controller comprising one or more processors, wherein the one or more processors are configured to perform controller operations comprising:
• generating a first plurality of sets of probe measurements for a plurality of sample locations located across a surface of a sample, wherein generating, for a particular sample location, a particular set of probe measurements of the first plurality of sets of probe measurements comprises:
• generating a first probe measurement of the particular set of probe measurements by operating the infrared light emitter to illuminate the sample with infrared light at a first wavelength that varies at a first frequency and operating the actuated probe to measure a magnitude and phase of a variation in displacement of the surface of the sample over time at the particular sample location at the first frequency;
• and
• generating a second probe measurement of the particular set of probe measurements by operating the infrared light emitter to illuminate the sample with infrared light at the first wavelength that varies at a second frequency and operating the actuated probe to measure a magnitude and phase of a variation in displacement of the surface of the sample over time at the particular sample location at the second frequency, wherein the first frequency and the second frequency differ;
• and
• generating, based on the first plurality of sets of probe measurements, a three--dimensional tomographic map of absorption of infrared light at the first wavelength by the sample.

A method for nanoscale tomographic imaging of heat dissipation in an electronic device, the method comprising:

• generating a first plurality of sets of probe measurements for a plurality of sample locations located across a surface of an electronic device, wherein generating, for a particular sample location, a particular set of probe measurements of the first plurality of sets of probe measurements comprises:
• generating a first probe measurement of the particular set of probe measurements by operating the electronic device to dissipate heat in a manner that varies at a first frequency and measuring a magnitude and phase of a variation in displacement of the surface of the electronic device over time at the particular sample location at the first frequency;
• and
• generating a second probe measurement of the particular set of probe measurements by operating the electronic device to dissipate heat in a manner that varies at a second frequency and measuring a magnitude and phase of a variation in displacement of the surface of the electronic device over time at the particular sample location at the second frequency, wherein the first frequency and the second frequency differ;
• and
• generating, based on the first plurality of sets of probe measurements, a three-dimensional tomographic map of dissipation of heat by the electronic device.