Summary: Integrated Optical Micro Systems
(for students of Electrical Engineering, Physics, Nanotechnology, and other related fields)
Improvement of the electro-optic modulator response of
the spiral-shaped Mach-Zehnder interferometric sensor
The spiral-shaped Mach-Zehnder interferometric sensor (sMZI sensor) has the potential for achieving a better
resolution. Current state-of-the-art is a refrective index resolution of n = 10-8
, which is equal to a detectable
change of v = 2 m/s in the speed of light (300,000,000 m/s). The goal of the project is to realise a sensor array,
which is fed by a single light source and read-out with a single detector.
An important element of the sMZI sensor is the electro-optical modulator based on ZnO. The functions of the
modulator are (a) to utilise the most accurate sensing region, and (b) enables higher phase accuracy by using a
clever modulation scheme.
Besides a linear electro-optic material, ZnO is also a semiconductor. A model has been made of the relation
between the (electro-)optical properties of ZnO, and the semiconductive properties. This model has to be
verified, and this requires the design, realisation and characterisation of several electrical test structures.
These test structures will be used to characterise ZnO layers deposited by sputtering, by varying the deposition
parameters. It is known from literature that both n-type and p-type ZnO layers can be made. Once we know how