SLHC upgrade of the ATLAS SCT tracker

The LHC accelerators and detectors will be upgraded to the super LHC (SLHC) in two phases: in PHASE-I to the peak luminosities of ∼3×1034 cm−2 s−1 and in PHASE-II to ≥10×1034 cm−2 s−1, to collect proton–proton collision data of ∼3000 fb−1 per experiment. The complete inner trackers of the ATLAS detector will be replaced with new silicon pixels in the inner part and new silicon microstrip detectors in the outer part. The n-strips in the p-type material (“n-in-p”) microstrip sensors have been developed. The n-in-p sensor collects electrons, the faster signals, in the p–n junction side of the detector throughout its lifetime. Characterization of the wafer materials and the design of the strip sensors have advanced through the development of ATLAS05, ATLAS06, and ATLAS07 sensors. An n-in-p silicon microstrip sensor has been fabricated that tolerates bias voltage up to ∼1000 V, in 150-mm-diameter FZ wafers from industry.