Context
The target of i-FLEXIS is the development of an innovative, reliable and low-cost integrated X-ray sensor system based on heterogeneous inorganic, organic and hybrid components.
For example, X‐rays are used in Biomedicine (Radiography),
Radiotherapy (as a treatment
for the therapy, including palliation, of cancer), Industrial quality control
(automated inspection of
industrial parts) and Security applications (control of luggages, cargos trucks and even people, before
and during shipment by air, sea and road), and other niche but important applications in the
scientific field (like X‐ray crystallography, X‐ray fluorescence, X‐ray photoelectron spectroscopy,
Astronomy and Art ‐ paintings or sculptures are often X‐rayed to reveal features invisible to the
naked eye, like under‐drawings, alterations, restorations, etc).
Many of these applications would
take advantage of large area, thin and flexible ionizing radiation sensing systems able to operate at
room temperature and to detect X‐rays in real time at affordable costs, but the technologies today
available cannot deliver all these features in one single object.
Presently, the radiation detectors
available on the market are either based on gas‐filled containers (like Geiger counters), on solid or
liquid materials capable of producing visible photons upon exposure to the radiation (scintillators), or
on solid materials capable of directly converting X‐ray photons into an electrical signal. The latter
type of solid state sensors offers the great advantage to skip the need to employ two or more
coupled devices (e.g. a scintillator and a photodiode or a photomultiplier tube), which grants
satisfactory performances, but increases the device complexity (hence its maintenance and operating
costs) and lowers its overall efficiency.
The state‐of‐the‐art solid state X‐ray detectors are based on
inorganic materials (silicon, cadmium telluride, diamond, and the like), which indeed offer top
detecting performances but are rigid, heavy, expensive, energy‐consuming, and often require low temperature
cooling to work properly. Nonetheless, the market for X‐rays equipment, though not
easy to estimate, according to publicly available documents was worth about $10 billions in 2008,
with a steady growth per year of about 4‐6%. The key drivers for this growth were, and still are, the
increasingly aging population, which demand for more and more radiography applications, the
unavoidable transition from the rather obsolete photographic film technology to the digital one, the
increasing security needs after the terrorist act of 9/11, and a strong demand for portable, robust
and low‐cost X‐rays detectors. Therefore, there exists a very strong need to devise low‐cost,
conformable, large area and reliable alternatives to the current technology radiation detectors;
prospective low‐power consuming and portable (i.e. low weight and battery operated) sensing
systems would have an even higher commercial success, since no such device is yet available or
marketed.
i‐FLEXIS aims to fill these gaps, developing an innovative, large area and low‐cost integrated system for detecting X‐ray ionizing radiations, exploiting nanotechnology to obtain unprecedented functionalities with respect to the currently available technology and to fully meet the pressing demands from a broad range of applications spanning from health diagnostic, to industrial monitoring and to security control.
To implement this concept, i‐FLEXIS will exploit nanoscale organic and inorganic conducting, semiconducting and dielectric materials processed at low temperatures (< 150°C) on flexible largearea substrate foils like polyethyleneterephthalate (PET). These concepts, extremely innovative and of very recent achievement, have been so far demonstrated as a proof‐of‐principle operation at laboratory scale. In the i‐FLEXIS project they will be implemented into operational devices and improved in terms of performances and reliability exploiting nanotechnology and organic electronics cutting edge principles and approaches. They will be integrated into a single system capable of detecting X‐rays of different energies. The final integrated device will have performances and functionalities that go well beyond those inferable from the three single components, fully realizing the concept of "system integration synergy", and will be realized using industry‐ready fabrication techniques.