Optical microdisks for integrated devices

A method of operating an integrated device, the method comprising:

• delivering excitation radiation from an optical waveguide to a reaction chamber, wherein the optical waveguide and reaction chamber are integrated on a substrate of the integrated device;
• passing emission radiation from the reaction chamber through a microdisk to a sensor that is integrated on the substrate;
• and
• increasing with the microdisk an amount of the emission radiation received by the sensor compared to an amount of the emission radiation that would be received without the microdisk,
• wherein the microdisk comprises an oxide or nitride material.

A method for fabricating an integrated device, the method comprising:

• forming, at each of a plurality of pixels on a substrate, a reaction chamber, an optical waveguide arranged to deliver excitation radiation to the reaction chamber, and an optical sensor arranged to receive emission radiation from the reaction chamber;
• and
• forming a microdisk at each pixel between the optical waveguide and the optical sensor, wherein the microdisk is configured to increase an amount of the emission radiation that is received by the optical sensor compared to an amount of the emission radiation that would be received without the microdisk,
• wherein forming the microdisk comprises depositing a first dielectric material onto the substrate and etching said first dielectric material to form voids in the first dielectric material,
• wherein forming the microdisk further comprises filling the voids in the first dielectric material with a second material different than the first dielectric material, and
• wherein the first dielectric material has a first index of refraction and the second material has a second index of refraction different from the first index of refraction.