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Low Gain Avalanche Detectors (LGAD) are silicon particle sensors with intrinsic gain through a thin p-type multiplication layer inserted between n-type implant and p-type bulk. The first prototype of LGAD sensors in China have been developed at the Institute of High Energy Physics (IHEP) of Chinese Academic Sciences and the Novel Device Laboratory (NDL) of Beijing Normal University. With an active thickness of 33 μ m, good breakdown performance, gain > 10, these sensors have reached jitter contribution of 10 ps to timing resolution with laser tests.

In this paper, we compare two multi-guard ring geometries for n-on-p silicon particle detectors for high luminosity applications. One structure has p-type guard rings while the other has n-type guard rings with p-stop isolation between n+ implants. The pre-irradiation performance of the guard ring structures are studied as a function of oxide charge. It is found that for both structures, there is a value of oxide charge for which the breakdown voltage is maximum. The post-irradiation performance of the structures are evaluated with simulations up to a radiation fluence of 1×10+16 neq/cm2 using an existing three-level trap model for p-type FZ silicon. TCAD simulation has been used to simulate I-V characteristics, charge carrier concentration, electric field, and potential distribution.

Hyperpolarized silicon particles have been shown to exhibit long spin-lattice relaxation times at room temperature, making them interesting as novel MRI probes. Demonstrations of hyperpolarized silicon particle imaging have focused on large micron size particles (average particle size (APS) = 2.2 μm) as they have, to date, demonstrated much larger polarizations than nanoparticles. We show that also much smaller silicon-29 particles (APS = 55 ± 12 nm) can be hyperpolarized with superior properties. A maximum polarization of 12.6% in the solid state is reported with a spin-lattice relaxation time of 42 min at room temperature thereby opening a new window for MRI applications., Scientific Reports, 7, ISSN:2045-2322

This paper presents a comparative study for two different n-in-p silicon particle detector structures in the purpose of evaluating the breakdown voltage of unirradiated devices candidate for high luminosity applications. The two structures based on the n-in-p technology with and without p-spray isolation between guard rings have been simulated on high resistivity silicon wafers. The simulated electrical characteristics current-voltage, for both structures, are compared for various parameters like, substrate thickness, substrate doping, guard ring depth, guard ring doping, oxide thickness, and oxide charge, under similar conditions. From the results of the simulation, we conclude that, in terms of leakage current, both structures behave similarly but in terms of breakdown voltage, n-in-p technology with p-spray shows better performances.

Printed electronics are considered for wireless electronic tags and sensors within the future Internet-of-things (IoT) concept. As a consequence of the low charge carrier mobility of present printable organic and inorganic semiconductors, the operational frequency of printed rectifiers is not high enough to enable direct communication and powering between mobile phones and printed e-tags. Here, we report an all-printed diode operating up to 1.6 GHz. The device, based on two stacked layers of Si and NbSi2 particles, is manufactured on a flexible substrate at low temperature and in ambient atmosphere. The high charge carrier mobility of the Si microparticles allows device operation to occur in the charge injection-limited regime. The asymmetry of the oxide layers in the resulting device stack leads to rectification of tunneling current. Printed diodes were combined with antennas and electrochromic displays to form an all-printed e-tag. The harvested signal from a Global System for Mobile Communications mobile phone was used to update the display. Our findings demonstrate a new communication pathway for printed electronics within IoT applications. Funding Agencies|Knut and Alice Wallenberg Foundation (Power Paper Project) [KAW 2011.0050]; Onnesjo Foundation; Swedish Research Council Linnaeus Grant LiLi-NFM; European Regional Development Fund through Tillvaxtverket (Project PEA-PPP)

Nanovectors are powerful tools for the systemic delivery of therapeutic and imaging agents in oncology. We have recently introduced multistage nanovectors (MSV), designed to overcome sequential biological barriers. The first stage, comprised of porous silicon microparticles, targets tumor-associated endothelium. Once arrested at the disease site, second-stage nanoparticles carrying the therapeutic and imaging agents are released into the tumor microenvironment by time-dependent degradation of the silicon carrier. Particles–cell interactions and degradation of MSV can be controlled by means of particle surface modifications. In this chapter, we will describe studies related to the MSV, focusing on fabrication, intracellular multisite trafficking, advanced therapeutic systems, and contrast agents.

A method for effectively utilizing a Scanning Electron Microscope (SEM) for defect review and identification of unpatterned silicon particle wafers, following inspection on a laser-scanning defect inspection tool, is presented. The method involves pre-patterning of bare silicon wafers at the extreme edges, typically less than 3 mm from the edge of a 200 mm wafer, using standard (I-Line) photolithographic processing. The registration marks created in this process are used for stage correlation between the SEM and laser-scanning wafer inspection tools. Use of these marks is demonstrated to result in a 50% improvement in particle location accuracy (mean+2 sigma) over previously reported results. Further optimizations, including modeling and removal of systematic error sources through data transformations, demonstrate the additional improvements in particle location accuracy that are possible.

A method for effectively utilizing a Scanning Electron Microscope (SEM) for defect review and identification of unpatterned silicon particle wafers, following inspection on a laser-scanning defect inspection tool, is presented. The method involves prepatterning of bare silicon wafers at the extreme edges, typically less than 20 mm from the edge of a 200 mm wafer, using standard (I-Line) photolithographic processing. The registration marks created in this process are used for stage correlation between the SEM and laser-scanning wafer inspection tools. Use of these marks is demonstrated to result in a 50% improvement in particle location accuracy (mean + 2 sigma) over previously reported results. Further optimizations, including modeling and removal of systematic error sources through data transformations, demonstrate the additional improvements in particle location accuracy that are possible.

Since the introduction of superlattices1 and quantum well structures,2 quantum confinement in man-made structures has been an important area of research in semiconductor physics and material science, as well as many new functional devices3 utilizing the discrete nature of these artificially created energy states. Before explaining the physics of extreme quantum confinement and its manifestation in the Si/a-SiO2 system, we shall first examine what assumptions are involved in conventional quantum confinement. The following assumptions and situations are applicable in conventional quantum confinement.

Not only for the development of a detector manufacturing process, but also for quality testing and radiation damage evaluation one needs appropriate test structures. These should be included in the wafer-scale devices. Several test structures have been studied in practice, especially the MOS capacitor and various small diodes. Also some effects from prolonged irradiation are reported.

Machining of aluminum alloys was the subject of a technical session at the Materials and Processing Show and Congress held in Chicago on November 13, 1979. This article presents some of the highlights on machining of aluminum alloys discussed at this session. The papers presented were: “Influence of Aluminum Casting Alloy Characteristics on Machinability” John L. Jorstad, Reynolds Metals Company “A Practical Approach to Aluminum Machining” Daniel R. Stashko, Valeron Corporation “Successful Broaching of Aluminum Automotive Engine Components” Myron J. Schmenk, Cincinnati Milacron “Drilling of 380 and 390 Aluminum” Thomas J. Skingle, Acme-Cleveland Corporation “The Skiving of Extruded Aluminum Tubing for Automotive Condenser Tubes” Robert B. Jagers, Chrysler Corporation “Ultra High-Speed Machining of Aluminum” Robert I. King, Lockheed Missile & Space Co.