Double-sided Microstrip Research Articles

Characterization of Tracking Modules Based on DSSD Sensors at the SC-1000 Accelerator for the BM@N Project

The results of studying characteristics of modules based on double-sided microstrip silicon sensors, which are designed to create the wide-aperture Silicon Tracking System for the BM@N facility, are presented. The main module features are the use of fast readout electronics based on the STS-XYTER chip and the application of ultralight (0.23% X0) aluminum microcables for transmitting analog signals from the sensor strips to the input channels of the readout electronics. The results of testing different configurations of tracking modules on the extracted beam of protons at the SC-1000 accelerator in the PNPI are presented. The stable operation of readout electronics is demonstrated at loads close to the maximum values of 360 kHz s–1 cm–2. The signal-to-noise ratio was no less than 23. The measured coordinate resolution of the modules within the beam telescope was 17 ± 0.4 μm, and the detector efficiency of recording for protons with energy of 1 GeV was no less than 99%.

From 3D to 5D tracking: SMX ASIC-based double-sided micro-strip detectors for comprehensive space, time, and energy measurements

We present the recent development of a lightweight detector capable of accurate spatial, timing, and amplitude resolution of charged particles. The technology is based on double-sided double-metal p+ – n – n+ micro-strip silicon sensors, ultra-light long aluminum-polyimide micro-cables for the analogue signal transfer, and a custom-developed SMX read-out ASIC capable of measurement of the time (Δt ≲ 5 ns) and amplitude. Dense detector integration enables a material budget > 0.3 % X 0. A sophisticated powering and grounding scheme keeps the noise under control.In addition to its primary application in Silicon Tracking System of the future CBM experiment in Darmstadt, our detector will be utilized in other research applications.

The data acquisition system for the PANDA Micro-Vertex Detector

The PANDA (antiProton ANnihilation at DArmstadt) experiment will study the strong interaction in annihilation reactions between an antiproton beam and a stationary cluster jet target. The PANDA detector will be composed of several sub-detectors designed for tracking, particle identification and calorimetry. The Micro-Vertex Detector (MVD) is the innermost part of the tracking system surrounding the interaction region, which is designed for precise vertex and tracking detection. It consists of silicon pixel and double-sided microstrip detectors. For the readout of the microstrip sensors an ASIC called ToASt (Torino Asic for Strip readout) is being developed in 0.11 μm CMOS technology at INFN Turin. The ASIC takes advantage of both Time-over-Threshold and Time-of-Arrival methods to accurately measure the event's energy and timestamp. To sustain the acquisition of the microstrip sensors a MDC (Module Data Concentrator) ASIC is under development at KIT. Up to eight ToASt front-ends' data streams are multiplexed, read out and processed by one MDC. The data of several MDCs are collected and processed by the off-detector readout card MMB (MVD Multiplexer Board), also under development at KIT. The processed data is then transferred via 100 GbE optical links to the computing nodes. The ToASt chips have been integrated with the FPGA implementation of the MDC to form the first fully functional detector module. Beam tests have been performed at the COSY facility in Jülich. This paper focuses on the design of MDC ASIC and MMB board, the integration with the ToASt and presents preliminary beam test results.

Quality Assurance Test System for Assembly of STS Modules for the BM@N Experiment

The Silicon Tracking System (STS) of the BM@N experiment will be based on modules with Double-Sided microstrip Silicon Detectors (DSSD) which have been initially developed for the CBM experiment at FAIR. Each module consists of a DSSD, two front-end boards with 8 ASICs each, and a set of low-mass aluminum microcables. During the module assembly the microcables are tab-bonded to the sensor and readout ASICs. The module has 1024 channels on each side of the sensor. For the quality assurance of the ultrasonic bonding process a dedicated procedure based on the noise per channel measurements with a Pogo Pin test device was developed.

Assembly Device for Supermodules of Silicon Tracking System of the BM@N Experiment

The silicon tracking system of the BM@N experiment consists of four stations based on double-sided microstrip silicon sensors. The sensors make it possible to obtain a spatial resolution for tracks of secondary charged particles up to 17 μm. Two ASIC boards, the input channels of which are connected to the strips with ultralight (0.23% X0) aluminum flex cables, are used to readout and process signals from both sides of the sensor. Such an assembly is called a module. Silicon sensors are mounted on lightweight carbon-fiber support trusses in a way that the dead zones at the edges are overlapped due to the tiled layout. The frontend electronics are housed in metal containers with a heat sink system located at the rare ends of the carbon-fiber support truss. A set of modules attached to the carbon-fiber support truss with two containers with readout electronics at the ends is called a supermodule. The accuracy of the sensor positioning in the station plane plays a crucial role in limiting the degrees of freedom of the parameters determined by the software during the final alignment of the tracking system elements. A special device that allows mounting sensors on a carbon fiber truss with an accuracy of up to 15 µm on a 1200 mm base is developed to assemble supermodules. The results of testing the device are given.

Система оцінки якості монолітних активних мікропіксельних детекторів

A system for quality assessment of micropixel detectors is presented. The system includes a laser scanning microprobe and a setup for studying the response of micro detectors to minimum ionizing particles. The results of the validation of the developed system indicate its suitability for assessing the quality of the latest monolithic active pixel sensors (MAPS), promising elements of large-area tracking systems for future high-energy physics experiments. Comparison of MAPS with the double-sided microstrip detectors of the CBM experiment (FAIR, Darmstadt) indicates the feasibility of the upgrade of its Silicon Tracking System using MAPS.

A Novel Collapsible Flat-Layered Metamaterial Gradient-Refractive-Index Lens Antenna

With the advent of small-scale satellite technologies, there has been significant interest in developing low-profile antennas. This article presents a novel collapsible flat-layered lens based on gradient-refractive-index (GRIN) metamaterials. The 3-D lens consists of multilayer double-sided microstrip square-rings units of variable sizes distributed on planar dielectric substrates to satisfy the required refractive index distribution. Adjacent layers can be stored compressed in a stacked configuration with minimal height, then deployed to an operational arrangement to their full dimensions and capabilities. The key factor in this design is the judicious choice of the discretized metamaterial unit cell such that neighboring layers are separated by an air gap, which allows the lens to collapse. A proof-of-concept prototype operating at 13.4 GHz with a 11.2 cm diameter and a height of 0.4 and 2.1 cm in collapsed and operational arrangement, respectively, was manufactured within fabrication tolerances. A resonant patch array feed was used and the lens antenna was measured in the UCLA Plane Bi-Polar Near-Field measurement range achieving a 23 dBi directivity and 22.2 dBi gain. The numerical and experimental results agree well and demonstrate that this new lens is advantageous in terms of low packaging height without compromising high-performance.

Novel high-density interconnection technology for the CBM Silicon Tracking System

In the Silicon Tracking System of the Compressed Baryonic Matter experiment at the future accelerator facility FAIR, double-sided microstrip sensors with sizes up to 62 x 124 mm will be connected to the readout electronics by means of up to 50 cm long lightweight microcables. The well-established aluminum to aluminum TAB bonding technology between die and microcable is highly manual and time-consuming. Therefore, a novel high-density interconnection technology based on a copper-polyimide flex microcable has been developed. It combines gold stud bumping on the die with solder paste printing on the microcable and a flip chip interconnection process. Shear strength and cross-section analysis have been performed on the bonded structures to optimize the solder paste reflow as well as the flip chip bonding process. First underfill application studies have been conducted successfully.

Evaluation of double-sided silicon microstrip sensor for the FOOT experiment

Abstract The goal of the FOOT (FragmentatiOn Of Target) experiment is to measure the fragmentation cross section of protons into H, C, O targets at beam energies of interest for hadrontherapy (50–250 MeV for protons and 50–400 MeV/u for Carbon ions) (Tommasino et al., 2015 [1] ; FOOT CDR Conceptual Design, 0000 [2] ). Given the short range of the fragments, an inverse kinematic approach has been chosen, hence requiring precise tracking capabilities for charged ions. One of the foreseen experiment subsystems will be the MSD (Microstrip Silicon Detector), composed of three x – y measuring planes. In this work we evaluate the suitability of standard double-sided microstrip detectors, coupled to an high dynamic range readout chip, to be used for this task. The results about cluster signal, signal/noise, and dynamic range of readout chip are encouraging, and confirm the suitability of this class of sensors to be used in the FOOT experiment.

Design of an Ultra-wideband Transition from Double-sided Microstrip to Parallel-strip line for Balanced-type Antenna

Design of an Ultra-wideband Transition from Double-sided Microstrip to Parallel-strip line for Balanced-type Antenna

Belle II silicon vertex detector

The Belle II experiment at the SuperKEKB collider in Japan is designed to indirectly probe new physics using approximately 50 times the data recorded by its predecessor. An accurate determination of the decay-point position of subatomic particles such as beauty and charm hadrons as well as a precise measurement of low-momentum charged particles will play a key role in this pursuit. These will be accomplished by an inner tracking device comprising two layers of pixelated silicon detector and four layers of silicon vertex detector based on double-sided microstrip sensors. We describe herein the design, prototyping and construction efforts of the Belle-II silicon vertex detector.

Physics performance with the ALICE silicon tracker

The detailed characterization of the quark gluon plasma (QGP) produced in heavy-ion collisions is the main goal of the ALICE experiment at the CERN LHC . The analysis of heavy quarks via the decays of the corresponding short-lived hadrons is among the prominent measurements to address the properties of QGP . To efficiently reconstruct these decays, the ALICE apparatus comprises a precise Inner Tracking System (ITS) made out of six layers of silicon detectors based on three different technologies, namely two layers of pixels, two of drifts and two of double-sided microstrip, listed in the order they are crossed by particles produced in the beam collision. In this paper, the contribution of the ITS to some of the main physics measurements that have been accomplished with proton and lead beams by the ALICE experiment will be discussed.

Systematic characterization and quality assurance of silicon micro-strip sensors for the Silicon Tracking System of the CBM experiment

The Silicon Tracking System (STS) is the central detector of the Compressed Baryonic Matter (CBM) experiment at future Facility for Anti-proton and Ion Research (FAIR) at Darmstadt.The task of the STS is to reconstruct trajectories of chargedparticles originating at relatively high multiplicities from the highrate beam-target interactions. The tracker comprises of 300 μmthick silicon double-sided micro-strip sensors. These sensors shouldbe radiation hard in order to reconstruct charged particles up to amaximum radiation dose of 1 × 1014neqcm−2. Systematiccharacterization allows us to investigate the sensor response andperform quality assurance (QA) tests. In this paper, systematiccharacterization of prototype double-sided silicon micro-strip sensorswill be discussed. This procedure includes visual, passive electrical,and radiation hardness test. Presented results include tests on threedifferent prototypes of silicon micro-strip sensors.

Total and Partial Fragmentation Cross-Section of 500 MeV/nucleon Carbon Ions on Different Target Materials

By using an experimental setup based on thin and thick double-sided microstrip silicon detectors, it has been possible to identify the fragmentation products due to the interaction of very high energy primary ions on different targets. Here we report total and partial cross-sections measured at GSI (Gesellschaft fur Schwerionenforschung), Darmstadt, for 500 MeV/n energy $^{12}C$ beam incident on water (in flasks), polyethylene, lucite, silicon carbide, graphite, aluminium, copper, iron, tin, tantalum and lead targets. The results are compared to the predictions of GEANT4 (v4.9.4) and FLUKA (v11.2) Monte Carlo simulation programs.

The Micro-Vertex-Detector for the P̄ANDA experiment

P̄ANDA is a fixed target experiment that will be carried out at the future FAIR facility. P̄ANDA will provide an excellent tool to address fundamental question in the field of hadronic physics, with a physic program that extends from the investigation of QCD (providing insight in the mechanisms of mass generation and confinement) to the test of fundamental symmetries.The Micro-Vertex-Detector located in the innermost part of the central tracking system will be composed by hybrid pixel and double-sided micro-strip silicon detectors. The Micro-Vertex-Detector will play an important role for the P̄ANDA physics goals. The possibility to reconstruct the secondary vertices and the applicability of a precise D meson tagging is essential for the spectroscopy in the open charm sector and the charmonium mass region. To this aim the Micro-Vertex-Detector features a spatial resolution better than 100μm, a time resolution better than 20ns, a limited material budget, and a high data rate capability in a triggerless environment. An overview of the Micro-Vertex-Detector related to the physics goals will be presented.

공통 결함접지구조를 이용한 링 하이브리드 커플러의 소형화 설계

This paper describes the design of size-reduced ring hybrid couplers (RHC) using a common defected ground structure (CDGS). The proposed RHC consists of double-sided microstrip line and the CDGS patterns which are placed in the common ground plane of the double-sided microstrip line. The effects of DGS as a periodic structure are imposed on both microstrip lines, so the advantages of the existing DGS are doubled. The normal RHC is designed first and folded by the half reference plane with the CDGS realized on the common ground plane. So another trial for size-reduction is performed by folding the RHC and inserting CDGS besides to the conventional DGS. In order to show a design example, a 2GHz RHC is designed and miniaturized using CDGS. The size of the miniaturized RHS is around 50% of the normal one, while the performances are well preserved even after the size-reduction.

Optimization of Strip Isolation for Silicon Sensors

Abstract Precision machines like electron-positron-colliders and b-factories demand for low material budget and high position resolution when it comes to particle tracking. A low material budget can be achieved by using thin double-sided silicon detectors (DSSDs) and lightweight construction. Since thin sensors give low signals, one has to be very careful to achieve high charge collection efficiency, which requires an appropriate sensor design. In this paper we present a detailed investigation of different p-stop patterns used for strip isolation on the n-side of double-sided microstrip sensors with n-type bulk. We designed test sensors featuring the common p-stop, the atoll p-stop and a combined p-stop pattern, and for every pattern four different geometric layouts were considered. These sensors were tested at the Super Proton Synchrotron (SPS) at CERN (Geneva, Switzerland) in a 120 GeV/c hadron beam. Then they were irradiated to 700 kGy with a 60 Co source and subsequently tested in the same beam as before. One geometric layout of the atoll p-stop pattern turned out to perform best, both before and after irradiation. The conclusions of these tests will be applied to the design of DSSDs for the Belle II experiment at KEK (Tsukuba, Japan).

공통 결함접지구조를 이용한 소형화된 저역통과여파기의 설계

This paper describes and presents the design of a miniaturized low pass filter (LPF) for microwave frequency region using a common defected ground structure (CDGS). In this study a half-sized LPF is obtained using CDGS, while the previous LPFs with the conventional DGS showed a mild size-reduction. The common DGS (CDGS) is realized on the common ground plane of two microstrip lines, i. e double-sided microstrip lines, which exist back-to-back to each other. In order to show the validity of the proposed design, an example of LPF using CDGS and double-sided microstrip lines is designed, fabricated and measured using the dielectric substrate with the dielectric constant of 2.2 and with the thickness of 31mils. The size of the designed LPF using CDGS is only 52.6% compared to that of the previous LPF with the conventional DGS. In addition, it is shown that the performances of the proposed LPF are well preserved after the size-reduction with the measured S11 and S21 of -22dB, min and -0.19dB, max, respectively.

Mechanics and detector integration in the P̄ANDA Micro-Vertex-Detector1

The Micro-Vertex-Detector (MVD) is the innermost detector of the P̄ANDA target spectrometer utilizing silicon hybrid pixel detectors and double-sided microstrip detectors in the inner and outer parts, respectively. The experimental setup requires sophisticated solutions for the detector integration in order to maintain a stringent material budget. Basic detector layout, the overall support concept and the integration of main detector parts are summarized in this article. First support components made of lightweight carbon structures have been manufactured. Selected parts of the prototype development will be presented. Finally, a conversion tool allows the migration of detailed CAD models to physics simulations. In this way the impact of engineering solutions on the overall detector performance can be checked.

Application of a thin double-sided microstrip detector for the registration of [formula omitted]-delayed charge particles: The 6He [formula omitted] decay into the two-body continuum of 6Li

We present a method for the detection of charged particles, emitted following β decay, that allows to reduce the background due to β radiation and thus to facilitate separation of the delayed-particle events. The isotopes of interest are implanted into a highly segmented double-sided silicon strip detector, resulting in excellent precision on the overall normalisation. The characteristics of the detector and the particle signatures are discussed. This method can be applied to a variety of systems close to the proton and neutron driplines; a region which the recent availability of post-accelerated radioactive beams has opened up for study. To demonstrate this, we measured the branching ratio of 6He β decay into the α + d two-body continuum of 6Li. We obtained a value of ( 1.7 ± 0.4 ) × 10 - 6 for energies α + d above 525 keV.