18-22 February 2019
Vienna University of Technology
Europe/Vienna timezone

Field effect transistor test structures for studies of inter-strip isolation in silicon strip detectors

Not scheduled
15m
Vienna University of Technology

Vienna University of Technology

Gusshausstraße 27-29, 1040 Wien
Board: 91
Poster Semiconductor Detectors Poster Session B

Speaker

Viktoria Hinger (Austrian Academy of Sciences (AT))

Description

Because of its radiation resilience, p-type silicon has been established as baseline material for tracking detectors in upcoming high-luminosity physics experiments. When deciding on the quality of p-type silicon strip sensors, strip isolation is crucial. Regions of highly doped p+ implant (p-stop) are introduced between n+ strips to interrupt the electron accumulation layer that forms at the interface to the overlying oxide. Doping concentration, implantation depth and geometry of the p-stop regions determine the achieved inter-strip resistance. Typically, inter-strip resistance is measured directly on the strip sensors. The measurement, however, is prone to substantial errors. Large resistances on the order of 100 GΩ require precise, low-noise measurement setups, which are influenced strongly by parasitic currents.
To provide a comparably simple alternative to measurements on strip sensors, this contribution aims to relate the threshold voltage and inter-channel resistance of field effect transistors (FET) to the inter-strip resistance of silicon strip sensors. We compare measurements of dedicated test structures to measurements on strip sensors with different n- and p-spray implantations and present comparative TCAD simulations. The FET test structures could present a fast and reliable option to judge inter-strip resistance and strip isolation properties on silicon sensors. This would be especially valuable for process quality control during future series productions.

Primary author

Viktoria Hinger (Austrian Academy of Sciences (AT))

Co-authors

Thomas Bergauer (Austrian Academy of Sciences (AT)) Dominic Blöch (HEPHY) Marko Dragicevic (HEPHY Vienna) Francesco Moscatelli (Universita e INFN, Perugia (IT)) Peter Paulitsch (Austrian Academy of Sciences (AT)) Manfred Valentan (Austrian Academy of Sciences (AT))

Presentation Materials