Silicon sensor development for the CMS tracker upgrade

Abstract

CMS started a campaign to identify the future silicon sensor technology baseline of the new tracker for the high-luminosity phase of LHC. We ordered a large variety of 6 inch wafers in different thicknesses and technologies at producer Hamamatsu. Thicknesses ranging from 50 microns to 300 microns are explored on Floatzone, Magnetic Czochralski and Epitaxial Silicon both in n-in-p and p-in-n versions. P-stop and p-spray are explored as isolation technologies for the n-in-p type sensors as well as the feasibility of double metal routing on 6 inch wafers. Each wafer contains many different structures to answer different questions, e.g. geometry, Lorentz angle, radiation tolerance, annealing behavior or read-out schemes. Dedicated process test-structures, as well as diodes, mini-sensors, long and very short strip sensors and real pixel sensors have been designed for this evaluation. This contribution provides an overview of the campaign and summarizes interesting measurements performed so far.