20-nm-Node trench-gate-self-aligned crystalline In-Ga-Zn-Oxide FET with high frequency and low off-state current

Tang

2021 IEEE International Symposium on Circuits and Systems (ISCAS)

et al. 2021

In the era of Intelligent IoT, huge amount of sensor data is collected and then transmitted to processor elements in edge devices or cloud servers. The latency and energy consumption in this process have been a bottleneck and are becoming more severe. To mitigate this problem, the idea of combining sensors, memory and processors for collectively handling the data, has been proposed and explored actively in recent efforts. In this work, thin-film transistor (TFT), which has been widely adopted in display devices and flexible sensors, is exploited. It is shown that, while TFT is promising for nearsensor processing architecture, it also shows a great potential for computing and storage for large-area and low-cost edge sensors. More specifically, we propose an almost-nonvolatile near-sensor computing-in-memory (CiM) array based on indium-galliumzinc-oxide (IGZO) TFT, and further, integrate the CiM array with a sensor array to be a sensing and data pre-process system. We show that such a TFT-based solution can accomplish realtime sensing and multiply-and-accumulate (MAC) processing in the analog field, which simplifies the system design with lowered energy and latency in our neural network evaluations.

Section: Introductionmentioning

confidence: 99%

Almost-Nonvolatile IGZO-TFT-Based Near-Sensor In-Memory Computing

Tang

2021 IEEE International Symposium on Circuits and Systems (ISCAS)

et al. 2021

IEEE Trans. Electron Devices

“…Nanocrystalline ZnO TFTs on high-resistivity silicon substrates have also demonstrated a high-frequency response (fT = 2.45 GHz, fmax = 7.45 GHz) [21]. High performance was also achieved by depositing c-axis aligned crystalline IGZO on heated substrate using a sophisticated nanoscale 3D gating structure [25]. However, single crystalline materials require complex and expensive deposition technique and hence are usually incompatible with low-cost, large-area manufacturing.…”

Section: Introductionmentioning

confidence: 99%

Amorphous-InGaZnO Thin-Film Transistors Operating Beyond 1 GHz Achieved by Optimizing the Channel and Gate Dimensions

Wang

Yang

Wang

et al. 2018

Amorphous indium-gallium-zinc oxide (a-InGaZnO or a-IGZO) has already started replacing amorphous silicon in backplane driver transistors for large-area displays. However, hardly any progress has been made to commercialize a-IGZO for electronic circuit applications mainly because a-IGZO transistors are not yet capable of operating at GHz frequencies. Here, nanoscale a-IGZO thin-film transistors (TFTs) are fabricated on a high-resistivity silicon substrate with a Ta2O5 gate dielectric. Carrier mobilities up to 18.2 cm 2 V-1 s-1 have been achieved. By optimization of the TFT channel length and contact overlap, we are able to demonstrate current-gain and power-gain cutoff frequencies at 1.24 and 1.14 GHz, respectively, both beyond the 1 GHz benchmark. Such a performance may have implications in developing at least medium-performance, a-IGZO-TFTs-based circuits for low-cost or flexible electronics.

Symp Digest of Tech Papers

“…But for the case of oxide TFTs, there is no junction in the device structure and the wide bandgap of channel material give great immunity for short channel effects. Very short channel oxide TFTs were already reported previously [2].…”

Section: Introductionmentioning

confidence: 99%

46‐2: Invited Paper: Ultimate Resolution Active Matrix Display with Oxide TFT Backplanes for Electronic Holographic Display

Hwang

Kim

Yang

et al. 2018

Oxide TFT backplane with 1μm channel length was developed for the application to electronic holographic display. Spatial light modulator (SLM) panel with 3μm pixel pitch was designed and successfully fabricated. The resolution of SLM panel was 16K by 3.2K and the diagonal length of active area was 2 inch. Fabricated SLM panel was ECB mode reflective type LCD panel, which could modulate the phase of incident light more than 2π. 3D image was successfully reconstructed with fabricated SLM panel. Vertical channel oxide TFTs are proposed for the switching device of 1μm pixel pitch. Oxide TFTs with ultra short channel length can be an enabler of the active matrix display with ultimate resolution.