Wireless Indium-Gallium-Zink-Oxide TranSceivers and Devices On Mechanically-Flexible Thin-Film Substrates (W I S D O M II)

在W I S D O M(第一阶段)，开发了一种全集成的柔性、非晶铟镓锌氧化物薄膜晶体管(TFT)电路技术。这些器件集成在可弯曲的50微米薄的聚酰亚胺薄膜上。对于栅长为0.5µm的TFT，测得其最大振荡频率(Fmax)达到300 MHz，渡越频率(FT)达到135 MHz，这是箔上IGZO TFT的世界纪录。此外，设计了栅长为2微米、成品率更高、85/40 MHz FMAX/FT的TFT，使至少有20个晶体管的IC能够实现。基于后一种技术，成功地演示和测试了用于数据通信的全集成发射机。它们基于工作在4 MHz左右的开关键控(OOK)调制器，该调制器在3V时仅消耗0.7 mA。此外，还设计了一种完全集成的无线可弯曲湿度传感器芯片，可用于智能尿布等应用。该芯片包括传感器、判决电路、OOK发射机、倍频器和天线。W I S D O M II(新二期)的重点将是开发工作在100 MHz和1 Mb/S的全集成可弯曲IGZO收发信机，该收发信机由优化的发射机和接收机组成。我们希望通过以下方式来推动工作频率：针对速度相关级的高速但更低良率晶体管的混合集成多达3 TFT；以及针对其余需要较低速度的电路的更高良率但较慢的晶体管，最多可达50 TFT，发射器中的倍频器(例如×8)，实现四倍频的正交振荡器，变频器优先与功放第二接收器，以及正反馈，以在维持稳定性的同时提高最高频率下的增益。此外，我们希望通过进一步缩短栅极长度(例如，使用聚焦离子束技术)、主动控制掺杂水平和陷阱以及减少接触寄生来提高TFT速度。根据FFlexCOM的设想，我们希望展示无线通信是可能的，只需使用一片可弯曲的塑料箔，而不需要任何刚性芯片，从而设想出可以轻松集成到纺织品中的完整通信收发器。

In W I S D O M (first phase) a fully integrated flexible, amorphous Indium-Gallium-Zinc-Oxide (IGZO) thin-film transistor (TFT) circuit technology was developed. The devices are integrated on a bendable 50 µm thin polyimide foil. A maximum frequency of oscillation (fmax) of up to 300 MHz and a transit frequency (fT) of up to 135 MHz were measured for TFTs with gate length of 0.5 µm. These results are world record values for IGZO TFTs on foil. Moreover, TFTs with gate length of 2 µm, higher yield and 85/40 MHz fmax/fT were designed enabling ICs with at least 20 transistors. Based on the latter technology, fully integrated transmitters for data communication are successfully demonstrated and measured. They are based on an on/off keying (OOK) modulator operating around 4 MHz which consumes only 0.7 mA at 3 V. Moreover, a fully integrated wireless bendable moisture sensor chip was designed envisioning e.g. the application for smart diapers. The chip includes the sensor, a decision circuit, an OOK transmitter, a frequency doubler and an antenna. Scalable compact models with good agreement between measured and simulated DC and high frequency characteristics were developed.The focus of W I S D O M II (new, second phase) will be on the development of a fully integrated bendable IGZO transceiver operating up to 100 MHz and 1 Mb/s, which consists of an optimized transmitter and receiver. We want to push the operating frequencies e.g. by: hybrid integration of our high speed but lower yield transistors for the speed relevant stages with up to 3 TFTs and the higher yield but slower transistors for the rest of the circuits requiring lower speed with up to 50 TFTs, frequency multipliers (e.g. × 8) in transmitters, quadrature oscillators enabling frequency quadruplication, frequency converter first and amplifier second receivers, and positive feedback to boost gain at highest frequencies while maintaining stability. Moreover, we want to improve the TFT speed, e.g. by further reduction of the gate length (e.g. with focussed ion beam techniques), active control of doping levels and traps, as well as reduction of contact parasitics. According to the FFlexCOM vision we want to show that wireless communication is possible using just a piece of bendable plastic foil without any rigid chips envisioning full communication transceivers which can be easily integrated in textiles.