  Silicon tracking detectors have grown to cover larger surface areas up to
hundreds of square meters, and are even taking over other sub-detectors, such
as calorimeters. However, further improvements in tracking detector performance
are more likely to arise from the ability to make a low mass detector comprised
of a high ratio of active sensor to dead materials, where dead materials
include electrical services, cooling, mechanical supports, etc. In addition,
the cost and time to build these detectors is currently large. Therefore,
advancements in the fundamental technology of tracking detectors may need to
look at a more transformative approach that enables extremely large area
coverage with minimal dead material and is easier and faster to build. The
advancement of thin film fabrication techniques has the potential to
revolutionize the next-to-next generation of particle detector experiments.
Some thin film deposition techniques have already been developed and widely
used in the industry to make LED screens for TV's and monitors. If large area
thin film detectors on the order of several square meters can be fabricated
with similar performance as current silicon technologies, they could be used in
future particle physics experiments. This paper aims to review the key
fundamental performance criteria of existing silicon detectors and past
research to use thin films and other semi-conductor materials as particle
detectors in order to explore the important considerations and challenges to
pursue thin film detectors.
