In this study, we propose newly designed feedback field-effect transistors that utilize the positive feedback of charge carriers in single-gated silicon channels to achieve steep switching behaviors. The band diagram, I-V characteristics, subthreshold swing, and on/off current ratio are analyzed using a commercial device simulator. Our proposed feedback field-effect transistors exhibit subthreshold swings of less than 0.1 mV dec, an on/off current ratio of approximately 10, and an on-current of approximately 10 A at room temperature, demonstrating that the switching characteristics are superior to those of other silicon-based devices. In addition, the device parameters that affect the device performance, hysteresis characteristics, and temperature-dependent device characteristics are discussed in detail.

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In this study, we demonstrate the abruptly steep-switching characteristics of a feedback field-effect transistor (FBFET) with a channel consisting of a p(+)-i-n(+) Si nanowire (NW) and charge spacers of discrete nanocrystals on a plastic substrate. The NW FBFET shows superior switching characteristics such as an on/off current ratio of ∼10(5) and an average subthreshold swing (SS) of 30.2 mV/dec at room temperature. Moreover, the average SS and threshold voltage values can be adjusted by programming. These sharp switching characteristics originate from a positive feedback loop generated by potential barriers in the intrinsic channel area. This paper describes in detail the switching mechanism of our device.

of conventional memory are advantages of SRAM and DRAM over new alternatives. Therefore, they will retain their mainstream position in the memory industry for the foreseeable future. Technologies have been proposed to solve the aforementioned limitations of traditional memory devices, such as removing the storage capacitor of DRAM [16,17] and reducing the number of transistors of SRAM. [18] In this study, we demonstrate a switchable-memory transistor with a p + -i-n + doped silicon nanowire whose fabrication process is fully compatible with silicon-based complementary metal-oxide semiconductor (CMOS) technology. The outstanding memory characteristics originate from the positive feedback loop in the intrinsic channel. Notably, our single device not only reduces the number of transistors (constituting a single SRAM cell) in the memory device but also operates the switching function. This is one of the novel strengths of our switchable-memory device for future electronics, as conventional memory devices only provide the function of data storage. The decrease in the number of transistors and the operation of multiple functions can be beneficial for scaling the memory device with regard to the total chip size and power consumption. Hence, we propose a feedback field-effect transistor (FET) with a dual top-gated silicon nanowire channel to enable the switching and memory functions in a single transistor. Results and DiscussionWe demonstrate the switchable-memory characteristics of a silicon nanowire transistor with a dual-gate structure. Figure 1 shows schematic and optical images of our transistor, which consists of a silicon nanowire channel and dual-gate electrodes. On the upper side of the channel region (6 µm long), two gate electrodes (each 2 µm wide) are arranged side by side. The gate electrode located near the p + doped region is named "Gate1 (V G1 )," and the other gate electrode located near the n + doped region is named "Gate2 (V G2 )." Details regarding the fabrication are presented in Experimental Section. Our switchable-memory transistor can be fabricated using conventional CMOS technology, which is clearly advantageous for industrial applications.As shown in Figure 2a, when V DS is swept from −0.1 to 4.1 V and then back to −0.1 V as a function of V G1 and V G2 , our transistor shows bistable I DS -V DS characteristics owing to the similar structures of thin capacitively-coupled thyristor (TCCT) devices [19][20][21] and field-effect diodes. [22,23] Without gate bias voltages, the transistor exhibits ordinary p-n diode characteristics;The switchable-memory operation of a feedback silicon nanowire transistor with a dual-gate structure is demonstrated. The single transistor exhibits volatile memory characteristics with a retention time longer than 3600 s, as well as a switching capability with a subthreshold swing lower than 7 mV dec −1 . A gate-controlled memory window forms around a gate voltage of 0 V owing to the positive feedback loop in the channel region, allowing a program/erase endurance of more th...

Objective: To investigate the effects of cavitating lesions involving the internal auditory canal (IAC) in subjects with cochlear otosclerosis with regard to poststapedotomy hearing outcome. Study Design: Retrospective study. Setting: Tertiary referral center. Patients: A retrospective chart review of 134 subjects with otosclerosis treated from January 2011 to June 2017 at Seoul National University Bundang Hospital was conducted. Sixteen subjects (23 ears) with temporal bone computed tomography (TBCT)-confirmed cochlear otosclerosis who underwent stapedotomy were included in the study. Main Outcome Measures: Pure tone audiometry (PTA) (i.e., air and bone conduction; AC and BC, respectively) thresholds and air–bone gap (ABG), measured at 6 months postoperatively were compared between cochlear otosclerosis with and without IAC involvement (IAC group and non-IAC group, respectively). Results: A total of 14 of 23 ears showed involvement of the IAC. There were no significant differences in age, side of otosclerosis, or preoperative hearing threshold between the two groups. The mean postoperative AC and BC thresholds and ABG of the IAC group were significantly poorer (45.7 dB, 33.8 dB, and 11.8 dB, respectively) than those of the nonIAC group (24.1 dB, 20.0 dB, and 4.1 dB, respectively). Conclusions: Cochlear otosclerosis with cavitating lesions involving the IAC showed significantly poorer postoperative audiological outcomes than those without any cavitating lesion. Cavitation extending to the IAC may act as a third window providing a route for sound energy shunting, and thus precluding successful hearing outcome in some subjects with cavitating otosclerosis after stapedotomy.