This paper reports on the use of 10 B nano/microparticles in order to fill microstructures of deep trenches fabricated in n-type Si (110) bulk wafers for the development of solid-state thermal neutron detectors. The high aspect-ratio trenches were fabricated in the wafer by wet etching, with a trench width of 3.5 to 6 lm and a maximum depth of 120 lm. Boron was diffused at a temperature of $1000 C in order to convert the entirety of the delicate Si microstructures into a p þ -n junction diode. The deep trenches of the diode were completely filled with 10 B nanoparticles using a simple room-temperature process involving the pumping and venting of a vacuum chamber containing the etched wafer with 10 B nanoparticles atop. The simple filling process was reproduced consistently, and the best 2.5 Â 2.5 mm 2 device demonstrated an intrinsic thermal neutron (E n < 0.5 eV) detection efficiency of 32.2 6 1.5% under a self-biased condition. This result is promising as it demonstrates a complete, low-cost fabrication process for the development of efficient thermal neutron detectors.Published by AIP Publishing. [http://dx.
Unipolar resistive switching behaviors including bistable memory switching and monostable threshold switching were found in ZrO2 thin films fabricated by a simple sol–gel method with the Ti/ZrO2/Pt structure. The multilevel resistive switching behaviors were also revealed by varying the compliance current from 9 to 38 mA. Physical mechanisms based on a conductive filament model were proposed to explain the resistive switching phenomena and the device breakdown. A figure of merit Z = ρa/ρf was defined as a criterion for evaluating OFF/ON resistance ratio, where ρf and ρa represent the resistivities of the conductive filament and the fracture region of the filament, respectively. The advantages such as unipolar resistive switching, multilevel resistive switching, good scalability, low operation voltage (<5 V), high OFF/ON resistance ratio (>103), nondestructive readout, long retention (>104 s), and simple fabrication method make the ZrO2-based resistive switching device a promising candidate for next-generation nonvolatile memory applications.
Double-sided module exhibits electrical and thermal characteristics that are superior to wire-bonded counterpart. Such structure, however, induces more than twice the thermo-mechanical stress in a single-layer structure. Compressive posts have been developed and integrated into the double-sided module to reduce the stress to a level acceptable by silicon dice. For a 14 mm x 21 mm module carrying 6.6 mm x 6.6 mm die, finite-element simulation suggested an optimal design having four posts located 1 mm from the die; the z-direction stress at the chip was reduced from 17 MPa to 0.6 MPa.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.