全氧化物積體電路開發：低成本可撓式射頻辨識標籤晶片

Abstract

以氧化物為基礎的電阻式記憶體，薄膜二極體以及薄膜場效電晶體，因為其簡單的結構、不受限於單晶基板的低溫製程、透明、優異的電特性等優點，近來來備受學術界與產業界關注，幾乎目前積體電路上可見的矽電子元件皆可由相對應的氧化物元件來取代，實現所謂的全氧化物積體電路。目前全氧化物積體電路的發展與應用尚在萌芽的階段，深具研究價值與產業佈局的戰略意義，預期將在未來超高密度記憶體、高整合密度的三維堆疊架構、新世代顯示器、可撓式電子、低成本拋棄式晶片的發展上扮演著非常重要的角色。過去三年中，我們研究團隊在國科會的支持下，積極投入此新穎且重要的研究工作，目前在電阻式記憶體，薄膜二極體，薄膜場效電晶體及三維堆疊可撓式電路上皆取得相當成果，為國內極少數具有全氧化物晶片製程整合能力的團隊，放眼國際亦享有領先地位。 本計畫最主要的目的在利用我們過去在氧化物電子元件上的經驗，一方面持續開發適用於軟性基板上的低溫甚至室溫成長的各式氧化物元件，並與美國SEMATECH進行合作交流，SEMATECH為目前先進半導體研究的重要基地與分享平台，這是將我們的研究方向與國際接軌，研究成果推向國際的難得契機。另一方面整合個別元件驗證一低成本可撓式的全氧化物積體電路技術。在諸多可能的電路應用中，本計畫預計以射頻辨識(RFID)標籤晶片為驗證的平台，射頻辨識為目前半導體產業中發展最迅速的領域，近年來利用射頻辨識技術進行大規模之單品追蹤應用，無論在研究或產業應用上都引起了廣泛的興趣，而亟待突破的技術瓶頸為昂貴的標籤晶片，本計畫針對此提出一成長於軟性基板上低成本全氧化物積體電路的解決方案，計畫完成射頻辨識標籤中雙半波整流器、環型振盪器、電阻式記憶體等關鍵電路模組開發，最後整合一包含了天線、電源、邏輯、記憶體等所有功能區塊的測試結構，驗證射頻辨識標籤以低成本可撓式全氧化物電路實現的可行性。

Oxide-based resistive-switching random access memory (RRAM), thin-film diode (OxTFD), and thin-film transistor (OxTFT) has attracted great attention recently in both research and industrial communities, owing to their simple structures, low-temperature and substrate-independent processes, transparency, and excellent electrical properties. Almost every single device in today’s silicon integrated circuits (ICs) could be replaced by the corresponding oxide device to realize the so-called all-oxide ICs. The development of the all-oxide ICs is still at its early stage with abundant research opportunities. It is expected to play a crucial role in the future ultra-high density memory, 3D stacking architecture, new- generation display technology, flexible electronics, and disposable electronics, all strategically important for the electronic industry in Taiwan. Supported by National Science Council in the past three years, we have been actively engaged in this novel field and making significant progress on RRAM, OxTFD, OxTFT, and 3D stacked flexible circuits. We are proud to be one of the very few groups in Taiwan with the full integration capability of all-oxide ICs, and now is also one of the leading groups in the world. By leveraging our existing expertise, the main objectives in this project are: First, develop oxide devices fabricated at low temperature or even at room temperature, applicable for flexible substrates. We will also cooperate with the U.S.-based SEMATECH, the leader of the advanced semiconductor R&D. This rare opportunity will help us connect and promote our research to the global stage. Second, integrate discrete oxide devices for a low-cost flexible all-oxide IC technology. Among many possible applications for all-oxide ICs, radio frequency identification (RFID) tag is chosen as an ideal test vehicle in this project. Today RFID represents one of the fastest-growing segments in the semiconductor industry. The RFID item-level tracking technology is of increasing interest in many real-world applications, but the development has been largely impeded by the high cost of RFID tags. We propose a solution based on the all-oxide RFID tag fabricated on low-cost flexible substrates. Critical circuit modules in RFID tags such as double half-wave rectifier, ring oscillator, and RRAM will be demonstrated. At last, an integrated structure including all functional blocks in RFID tags, such as antenna, DC power, logic, and memory, will be tested to validate the feasibility of low-cost RFID tags based on the all-oxide IC technology.