A chip removal facility for indium bump bonded pixel detectors Airoldi, A.; Alimonti, G.; Amati, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2005, Letnik:
540, Številka:
2
Journal Article
Recenzirano
Yield maximization in multichip hybrid pixel sensors is a crucial issue in large volume productions planned for future High-Energy Physics experiments. Bump bonding process optimization can guarantee ...statistical single bump failure rates at the acceptable level of 10–100
ppm; nevertheless, systematic effects connected to process repeatability can affect the functionality of a full chip in a module to a much larger extent. Because of this, the reversibility of the bonding procedure has been investigated. A feasibility study on single chip assemblies for the ATLAS experiment has been successfully completed, proving the possibility of reworking. As a result of it, a dedicated facility has been conceptually designed, engineered and commissioned. The characteristics of the facility in terms of motion, temperature and tensile strength control are outlined, together with the main results.
The DELPHI pixels Becks, K.H.; Borghi, P.; Brunet, J.M. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
02/1997, Letnik:
386, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
To improve tracking in the very forward direction for running at LEP200, the angular acceptance of the DELPHI Vertex detector has been extended from 45° to 11° with respect to the beam axis. Pixel ...detector crowns cover the region between 25° and 13°. Due to very tight space and material thickness constraints it was necessary to develop new techniques (integrated busses in the detector substrate, high density layout on Kapton, etc.). About 1000 cm
2 of pixels are already installed and working in DELPHI. Techniques, tests and production of these detectors will be described, as well as the main problems encountered during this work.
Commissioning of the DELPHI Pixel Detector Becks, K.H; Brunet, J.M; Caccia, M ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
1998, Letnik:
418, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
The DELPHI Vertex Detector has been upgraded for LEP200 with 2 layers of pixel detectors and 2 layers of ministrips as endcaps, thus covering the polar angular range between 10° and 21° and allowing ...for standalone pattern recognition. During the 1995/96 shutdown the first 95 modules were installed and the installation was completed in May 97 with all 152 modules. Production yields and failures during the assembly will be presented. The detector operated at a threshold of around 9000 electrons resulting in a number of noisy pixels at the 10
−3 level. After masking these hot pixels in the readout, the remaining number of random hits per event is at the 10
−6 level. The observed resolution of about 100
μm is close to the expectation for binary readout. The track reconstruction efficiency increased by more than 100% in the central part of the forward tracker.
Progress in the construction of the DELPHI pixel detector Becks, K.H.; Borghi, P.; Caccia, M. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
08/1997, Letnik:
395, Številka:
3
Journal Article, Conference Proceeding
Recenzirano
The status of the pixel detector for the DELPHI Silicon Tracker is presented. The main characteristics of the detector, the readout chip and the assembly are summarized.
First results from the DELPHI pixel detector Becks, K.H.; Brunet, J.M.; Caccia, M. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
05/1998, Letnik:
409, Številka:
1-3
Journal Article, Conference Proceeding
Recenzirano
In 1996 the DELPHI experiment at LEP has upgraded its silicon tracker. In the forward region, pixel detectors were installed. The pixel commissioning and the first results are reported.
A set of teaching materials dealing with harmonic oscillations was developed as a part of a research project investigating the influence of different pedagogical tools on physics learning. The ...materials incorporate simulation software and laboratory activities associated with Teacher and Student Units. The project involved research groups at seven Italian universities and the materials have been trialled in high schools nation-wide. This paper describes the experimental protocol for the use of these materials in pilot classes and the evaluation of student learning and teacher training results. The intervention was found to improve physics education at school praxis level and to promote understanding of the content area as well as appreciation of the role of experiments and simulations in the construction of scientific knowledge. (Autorenreferat).
Silicon pixel sensors developed by the ATLAS collaboration to meet LHC requirements and to withstand hadronic irradiation to fluences of up to
10
15
n
eq
/
cm
2
have been evaluated using a test beam ...facility at CERN providing a magnetic field. The Lorentz angle was measured and found to alter from 9.0° before irradiation, when the detectors operated at
150
V
bias at
B=1.48
T
, to 3.1° after irradiation and operating at
600
V
bias at
1.01
T
. In addition to the effect due to magnetic field variation, this change is explained by the variation of the electric field inside the detectors arising from the different bias conditions.
The depletion depths of irradiated sensors at various bias voltages were also measured. At
600
V
bias
280
μm
thick sensors depleted to
≈200
μm
after irradiation at the design fluence of
1×10
15
1
MeV
n
eq
/
cm
2
and were almost fully depleted at a fluence of
0.5×10
15
1
MeV
n
eq
/
cm
2
.
The spatial resolution was measured for angles of incidence between 0° and 30°. The optimal value was found to be better than
5.3
μm
before irradiation and
7.4
μm
after irradiation.
Beam test results from a prototype for the delphi microvertex detector
Nuclear instruments and methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment/Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/1990
Journal Article
The DELPHI silicon strip microvertex detector with double sided readout Chabaud, V.; Collins, P.; Dijkstra, H. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
01/1996, Letnik:
368, Številka:
2
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The silicon strip microvertex detector of the DELPHI experiment at the CERN LEP collider has been recently upgraded from two coordinates (RΦ only) to three coordinates reconstruction (RΦ and z). The ...new Microvertex detector consists of 125 952 readout channels, and uses novel techniques to obtain the third coordinate. These include the use of AC coupled double sided silicon detectors with strips orthogonal to each other on opposite sides of the detector wafer. The routing of signals from the z strips to the end of the detector modules is done with a second metal layer on the detector surface, thus keeping the material in the sensitive area to a minimum. Pairs of wafers are daisy chained, with the wafers within each pair flipped with respect to each other in order to minimize the load capacitance on the readout amplifiers. The design of the detector and its various components are described. Results on the performance of the new detector are presented, with special emphasis on alignment, intrinsic precision and impact parameter resolution. The new detector has been taking data since spring of 1994, performing up to design specifications.
Physics aspects of the DELPHI vertex detector
Nuclear instruments and methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment/Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/1989
Journal Article