Methods and apparatus for waveguide metrology

A waveguide metrology system, comprising:

• a light source coupled to a movable first stage and configured to transmit light towards a sample waveguide holder disposed on a second stage, the light source disposed on a first side of the second stage;
• one or more scatterometers coupled to a movable third stage on a second side of the second stage opposite the first side, the third stage separately movable from the first stage, the one or more scatterometers configured to collect light transmitted in a first direction from the sample waveguide holder towards the second side;
• one or more reflection detectors coupled to a movable fourth stage on the first side of the second stage, the fourth stage separately movable from the first stage and the third stage, the reflection detectors configured to collect light reflected in a second direction of from the sample waveguide holder towards the first side;
• and
• a spectrometer in communication with the one or more scatterometers and the one or more reflection detectors, wherein the system is configured to measure reflective and transmissive light diffraction efficiency characteristics of a sample waveguide in the sample waveguide holder.

A waveguide metrology system, comprising:

• a collimated light source coupled to a first movable stage;
• a sample waveguide holder disposed on a second movable stage;
• a reflection detector coupled to a third movable stage on a first side of the sample waveguide holder and configured to collect light reflected in a first direction from the sample waveguide holder;
• a transmission detector coupled to a fourth movable stage on a second side of the sample waveguide holder and configured to collect light transmitted in a second direction from the sample waveguide holder, wherein the first stage, the third stage, and the fourth stage are configured to revolve up to about 180° around the sample waveguide holder separate from any rotation by the second stage;
• and
• a spectrometer in communication with the reflection detector and the transmission detector, wherein the system is configured to measure reflective and transmissive light diffraction efficiency characteristics of a sample waveguide in the sample waveguide holder.