SYSTEM AND METHOD OF PERFORMING ATOMIC FORCE MEASUREMENTS
A system for performing atomic force measurements including: a sensor including: a beam having a first side and a second side, the beam including a tip positioned on a surface of the first side for interacting with a sample; and a grating structure positioned adjacent the second side of the beam, the grating structure including an interrogating grating coupler configured to direct light towards the beam; a light source optically coupled to an input of the sensor for inputting light; and an analyser coupled to an output of the sensor; wherein the beam and the interrogating grating coupler form a resonant cavity, a movement of the beam modulates the light source and the analyser determines a deflection of the beam according to the modulated light.
1 . A system for performing atomic force measurements including:
a sensor including:
a beam having a first side and a second side, the beam including a tip positioned on a surface of the first side for interacting with a sample; and
a grating structure positioned adjacent the second side of the beam, the grating structure including an interrogating grating coupler configured to direct light towards the beam;
a light source optically coupled to an input of the sensor for inputting light; and
an analyser coupled to an output of the sensor; wherein
the beam and the interrogating grating coupler form a resonant cavity, a movement of the beam modulates the light source and the analyser determines a deflection of the beam according to the modulated light.
2 . The system of claim 1 wherein the beam is a cantilever beam.
3 . The system of claim 1 wherein the beam is fixed at opposite ends.
4 . The system of claim 3 , wherein the beam includes a flexible portion between the ends
5 . The system of claim 3 wherein the tip is positioned between the two ends of the beam.
6 . The system of claim 1 wherein the modulated light is amplitude modulated.
7 . The system of claim 1 wherein the modulated light is frequency modulated.
8 . The system of claim 1 including a plurality of sensors.
9 . The system of claim 8 including a de-multiplexer wherein an input of the de-multiplexer is optically connected to the light source and each output of a plurality of outputs of the de-multiplexer is optically connected to a respective input of a grating structure of a respective sensor.
10 . The system of claim 8 further includes a multiplexer wherein each output of the plurality of grating structures of a respective sensor is optically connected to an input of the multiplexer, and the output of the multiplexer is connected to the analyser.
11 . The system of claim 9 wherein the de-multiplexer is a wavelength division de-multiplexer.
12 . The system of claim 11 wherein light input into the multiplexer is separated into a plurality of discrete wavelengths.
13 . The system of claim 11 wherein light input into the multiplexer is separated into a plurality of discrete wavelength bands.
14 . The system of claim 12 wherein each wavelength of the plurality of discrete wavelengths is modulated by a respective sensor.
15 . A method of performing atomic force measurements on a sample, the method including the steps of:
inputting light into a resonant cavity formed between a beam and a grating structure of a sensor;
receiving at an analyser light modulated by a movement of the beam; and
analysing the modulated light to determine a characteristic of the sample.
16 . The method of claim 14 wherein the characteristic is a topography of the sample.