Preliminary results of 3D-DDTC pixel detectors for the ATLAS upgrade

TL;DR

This paper presents preliminary experimental results on 3D-DDTC silicon pixel detectors, focusing on their electrical performance, charge collection, and testing in magnetic fields, for potential use in the ATLAS upgrade.

Contribution

It reports initial testing outcomes of 3D-DDTC pixel sensors with various column depths, highlighting their electrical and charge collection performance in a high-energy physics environment.

Findings

Leakage current and noise levels are within acceptable ranges.

Charge collection efficiency demonstrated with Sr90 beta-source.

Preliminary beam test results show promising detector performance.

Abstract

3D Silicon sensors fabricated at FBK-irst with the Double-side Double Type Column (DDTC) approach and columnar electrodes only partially etched through p-type substrates were tested in laboratory and in a 1.35 Tesla magnetic field with a 180GeV pion beam at CERN SPS. The substrate thickness of the sensors is about 200um, and different column depths are available, with overlaps between junction columns (etched from the front side) and ohmic columns (etched from the back side) in the range from 110um to 150um. The devices under test were bump bonded to the ATLAS Pixel readout chip (FEI3) at SELEX SI (Rome, Italy). We report leakage current and noise measurements, results of functional tests with Am241 gamma-ray sources, charge collection tests with Sr90 beta-source and an overview of preliminary results from the CERN beam test.