Eur. Phys. J. A (2015) 51: 15
https://doi.org/10.1140/epja/i2015-15015-2

Special Article - Tools for Experiment and Theory

Low-temperature technique of thin silicon ion implanted epitaxial detectors

¹ Heavy Ion Laboratory, Warsaw University, Warsaw, Poland
² LPC, IN2P3-CNRS, ENSICAEN, Université de Caen, F-14050, Caen-Cedex, France
³ “Horia Hulubei” National Institute of Physics and Nuclear Engineering (IFIN-HH), RO-077125, Bucharest Magurele, Romania
⁴ INFN and Università di Firenze, via G. Sansone 1, 50019, Sesto Fiorentino (Firenze), Italy
⁵ Institute of Experimental Physics, University of Warsaw, Warsaw, Poland
⁶ GANIL, CEA and IN2P3-CNRS, B.P. 5027, 14076, Caen-Cedex 05, France
⁷ Institut de Physique Nucléaire, IN2P3-CNRS, 91406, Orsay-Cedex, France
⁸ INFN and Dipartimento di Scienze Fisiche, Università di Napoli “Federico II”, Napoli, Italy
⁹ INFN and Università di Bologna, 40126, Bologna, Italy
¹⁰ LNS, INFN and Università di Catania, 95129, Catania, Italy
¹¹ INFN LNL Legnaro, viale dell’Università 2, 35020, Legnaro (Padova), Italy
¹² Jagiellonian University, Cracow, Poland
¹³ Silesian University, University of Silesia, Katowice, Poland
¹⁴ Institute of Electronic Materials Technology, Warsaw, Poland
¹⁵ Warsaw University of Technology, Faculty of Physics, Warsaw, Poland
¹⁶ Institute of Mikromechanics and Photonics, Department of Design of Precision Devices, Warsaw University of Technology, Faculty of Mechatronics, Warsaw, Poland

^* e-mail: kord@slcj.uw.edu.pl

Received: 30 October 2014
Revised: 15 January 2015
Accepted: 26 January 2015
Published online: 9 February 2015

Abstract

A new technique of large-area thin ion implanted silicon detectors has been developed within the R&D performed by the FAZIA Collaboration. The essence of the technique is the application of a low-temperature baking process instead of high-temperature annealing. This thermal treatment is performed after B⁺ ion implantation and Al evaporation of detector contacts, made by using a single adjusted Al mask. Extremely thin silicon pads can be therefore obtained. The thickness distribution along the X and Y directions was measured for a prototype chip by the energy loss of α-particles from ²⁴¹Am (〈E _α 〉 = 5.5 MeV). Preliminary tests on the first thin detector (area ≈ 20 × 20 mm²) were performed at the INFN-LNS cyclotron in Catania (Italy) using products emitted in the heavy-ion reaction ⁸⁴Kr (E = 35 A MeV) + ¹¹²Sn. The ΔE − E ion identification plot was obtained using a telescope consisting of our thin ΔE detector (21 μm thick) followed by a typical FAZIA 510 μm E detector of the same active area. The charge distribution of measured ions is presented together with a quantitative evaluation of the quality of the Z resolution. The threshold is lower than 2 A MeV depending on the ion charge.