LOW MASS LOW POWER RADIATION RESISTANT PIXEL MODULES

Particle physicists wish to reconstruct with high fidelity and 100% efficiency the trajectories of the products from physics interactions. For this the secret for success is well known: high-resolution minimal mass detector systems. While modern carbon composites, and novel cooling concepts enable a lower mass system, the key to low mass is a low power detector module.
This project addresses the key elements to obtain a low power pixel assembly by replacing the sensor element with a CMOS sensor. The CMOS sensor will also replace the first stage of the analogue amplification. This will reduce the power dissipated in the sensor and the readout electronics.
The CMOS sensors to be developed is based on an application of the HVCMOS technology commonly used for automotive electronics control. The HVCMOS sensor has a depleted sensing volume that allows fast and full charge collection even after irradiation. This is unlike most CMOS sensor technologies which rely on a slower drift process that is significantly affected by non-ionizing radiation damage.
The ROIC will still be used to process the data from the sensor as done in a standard pixel hybrid assembly. The advantage of this is to allow the full power of the ROIC to be utilized.
The HVCMOS sensor is attached with a simple glue joint to a standard Particle physics readout pixel chip. The signal is capacitivly coupled from the HVCMOS sensor to the ROIC. This simple assembly procedure, and cheap sensor, will significantly reduce the cost of the production of pixel modules which will allow them to be used more widely in particle physics experiments. Therefore extending the physics reach of a given experiment.
As the assembly procedure is very straight forward, gluing two items together, it will be possible to thin both the devices down to 50-100 micrometers each which will result in a mass reduction in the module.

The principal beneficiaries of this project will be the particle physics community through the development of a new cost-effective hybrid pixel detectors. The development such technologies has broader applications within science such as imaging at synchrotron sources and space missions, which can exploit the large area sensors with minimal dead area and/or the low power and mass of these innovative pixel modules.

Although the development of innovative detector technologies may appear somewhat remote to broader society, the results of the science that such technologies enable often have significant impact on society. The recent discovery of the Higgs' boson has captured the public's imagination and has, at least partially, to an increase in the number of young people pursing a physics degree. This built on a 10 year programme of detector development to build the world's biggest experiment: ATLAS. Similarly, the potential application of these detectors at synchrotron sources will impact on the society through the development of new materials, an increased understanding of biological processes and structures of drugs.