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We report on the photocurrent induced by 1550 nm laser irradiation in a Er-doped micron-scale silicon transistor. The erbium defects, activated in the channel of the transistor thanks to oxygen codoping, make it possible to observe a resonant photocurrent at telecom wavelength and at room temperature by using a supercontinuum laser source working in the $\mu\mathrm {W}$ range. By exploiting a back-gate, the transistor is tuned to exploit only the electrons lying in the Er-O states. We estimate a relatively small number of photoexcited atoms $(\sim 4\times 10^{4})$ making Er-dpoed silicon a candidate for designing resonance-based frequency selective single photon detectors at 1550 nm for quantum communications.

It has been reported that erbium (Er) is a source of optical emission at λ=1.54 pm due to 4I 13/2 →4I 15/2 transition of Er3+. A method of oxygen (O) codoping with Er has attracted attention as a candidate for obtaining more efficient optical gain by forming Er:O complex. Although several simulations predict the equilibrium structure of Er:O complex, it is difficult to understand experimentally how related between these implanted ions followed by annealing for optical activation. In this workshop, we reported the preliminary results on three-dimensional distributions of Er and O co-implanted into Si investigated by atom probe tomography.

Luminescence of erbium in silicon has been intensively explored in the past in the high power emission regime, but its employment for manufacturability of active components for silicon photonics proved unfeasible. We explore the room-temperature photoluminescence (PL) at the telecomm wavelength of very low implantation doses of ErO x in Si for accessing few photon regime towards single photon emission. We achieve countable photon regime and we assess the lower-bound number of detectable emission centers by micron scale implanted dots, whose emission is collected by an inverted confocal microscope.

Nanoscale electronic devices will require the placement of dopants in a predetermined location, namely, a single atom control to explore novel functions for future nanoelectronics. Deterministic doping method, i.e. single-ion implantation, realizes ordered arrays of single-atoms in silicon, diamond and other materials, which might provide opportunities to single-dopant transport or single-photon source beneficial to quantum processing.

Future CMOS will require the placement of dopants in a predetermined location, namely, a single atom control. Deterministic doping method, i.e. single-ion implantation, realizes ordered arrays of single-atoms in silicon, diamond and other materials, which might provide opportunities to single-dopant transport or single-photon source beneficial to quantum processing.

Si transistors with deterministically implanted donors were fabricated by single-ion implantation method and their quantum transport was investigated. By placing donors in one dimensional array, we observed the transport characteristics categorized into two regimes: single-electron tunneling through isolated D0 and D− states; Hubbard band formation due to the inter-donor coupling.

With the gate length of MOSFETs approaching 10 nm, the channel region contains only one or a few dopant atoms. Thus, the number and position of dopant atoms become critical factors in determining device performance. In previous work, we have revealed that the control of not only the dopant atom number but also its position is essential by experimentally for the first time [1]. A several theoretical analyses of random dopant fluctuation (RDF) effects have been presented since 1990s [2,3,4]. However, the effect of individual dopant positions on device electrical properties is not well understood experimentally. Here, we report the fabrication of transistors whose channel dopants are implanted one by one using single-ion implantation (SII) method [5,6,7]. Electrical measurements reveal that controlling of discrete dopant position serves to highlight the improvements in device transconductance.

A relative-story displacement sensor for measuring the ceiling-floor displacement and the floor inclination angle was developed. Three pairs of position-sensitive detector (PSD) units and light emitting diode (LED) arrays were utilized for the measurement. The measurement accuracy of the sensor was evaluated using a shaking table and a θ-stage. The outputs from the developed sensor agreed well with the reference, and the accuracy was evaluated to be approximately 0.15 mm in the displacement and 0.1 mrad in the local inclination angle. These results inidicate that the developed sensor resolves the angular error problem on the relative-story displacement measurement and is applicable for assessing the sefety of actual buildings.

Organosilane self-assembled monolayers (SAMs) have been utilized as one of the candidate for electron beam (EB) resist. Hydroxy-terminated SAM is much more sensitive to EB than vinyl-terminated one. This indicates that the sensitivity of SAMs to EB changes significantly depending on their type of terminal groups. However, the reason why the type of the terminal groups makes a difference of EB sensitivity is not understood yet. To clarify this reason, the effect of EB irradiation on SAMs by using infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), ellipsometry and contact angle measurement are discussed.