CMS Upgrade
The HIP CMS Upgrade project is responsible of the Finnish hardware contribution to the CMS experiment. Recently we finished the CMS Phase I Upgrade pixel sensor module production in Micronova Centre for Micro and Nanotechnology (located in Espoo, Finland) together with Advacam Ltd. In the Phase I Upgrade the innermost measuring element of the CMS detector, the silicon pixel detector, will be completely rebuilt and accompanied with new readout electronics capable of handling the continuously increasing amounts of data from the LHC machine. The number of channels, i.e. pixels and related interconnections, will simultaneously be increased from the current 64 million up to 125 million channels allowing significantly better tracking performance. The installation of the upgraded pixel detector into CMS will happen during the LHC winter stop in 2016-2017.
Our long-term R&D is focusing on the development of radiation hard silicon strip and pixel particle detectors for the future high luminosity HEP experiments. In 2001 we demonstrated the functionality of first radiation detectors made of high resistivity magnetic Czochralski silicon (MCz-Si). Later, in 2007, we measured a signal-to-noise ratio of about 15 from a full-size 768 channels n-type MCz-Si strip sensor after 1×1015 neq/cm2 proton irradiation by using Silicon Beam Telescope (SiBT) setup, situated at CERN H2 test beam area. Since 2006 we have carried out R&D for the development of next generation silicon pixel detectors together with the Laboratory of Inorganic Chemistry (HU), Accelerator Laboratory (HU) and Electron Physics Group of Aalto University. The research objective is to utilize Atomic Layer Deposition (ALD) method grown thin films for the effective capacitive coupling of the signal from measured particles. It is possible to produce very high capacitance density structures with ALD, which is a fundamental prerequisite for the high granularity pixel devices. In our approach the elevated leakage current is not directly connected into the read-out electronics like in the current pixel detectors and thus, allows significantly longer operation life-time of the pixel modules in a harsh radiation environment.