硫族金屬化合物在次世代記憶體之應用研究

Abstract

本計畫擬研究之硫族金屬化合物在次世代記憶體元件（包括導電橋式記憶體與相變 化記憶體）之應用，為因應元件尺寸之日益縮小，本計劃同時擬定奈米尺度之硫族金屬 化合物試樣製備、微結構與物理性質研究，以能對此一相變化材料在元件微縮的發展趨 勢中的應用特性有所了解。 本計劃第一年除延續既有之研究，探討之硫族金屬化合物的物理性質之改質，以累 積其在次世代記憶體之應用知識之外，並提出一套全自動之動/靜態元件量測系統之建置 構想，此系統並具備與表面漏電流原子力顯微鏡（Conductive AFM，CAFM）整合的能 力，以供後續微奈米記憶體元件之電與記憶轉換性質量測之用。第二年擬從事元件之電 極材料、熱傳導係數量測與元件熱模擬、電遷移及晶界擴散研究，以對未來元件製作之 材料選擇、製程整合與材料之長程可靠度能有了解。第三年則整合先前研究成果，進行 CBRAM 和PRAM 元件之製作與記錄機制研究，擬製備微奈米級之記憶胞元件，以自組 完成之進階動/靜態元件量測系統進行元件靜態I–V 特性量測、動態之擦寫電壓脈衝值量 測、動態擦寫電壓衝脈衝頻率量測、重覆擦寫次數量測、元件失效、疲勞與轉換機制等 之分析，並搭配適當之材料微結構與組成之分析，以了解元件結構與性質之相互影響關 係，而能對元件之微縮與CBRAM 和PRAM 之開發能有所貢獻。

The research of this project aims at the applications of chalcogenides to next-generation memory devices including conductive bridging random access memory (CBRAM) and phase-change random access memory (PRAM). The preparation, microstructure and physical properties of nano-scale chalcogenides will also be investigated so as to explore their applicability under the development trend of device scale-down. In first year of study, physical property modification of chalcogenides will be performed based on previous research established in our laboratory. In addition to the accumulation of knowledge applied to next-generation memory devices, this project intends to establish an advanced static/dynamic device property measurement system. This self-assembly system will also be integrated with conductive atomic force microscopy (CAFM) for analyzing the electrical performance of nano-scale memory cells. Characterization of electrode materials, thermal analysis of memory device, electromigration and grain-boundary diffusion in the phase-change materials will be the main themes of second-year project so as to secure the knowledge of material selection, thermal conductivity and device thermal simulation, and long-term reliability of chalcogenides. All analytical results obtained in previous years will be integrated in third year and implant in the preparation and characterizations of CBRAM and PRAM. The device property measurement system established in first yrear will be utilized to investigate the static I-V profiles, dynamic write/erase properties, cycleabiltiy, fatigue/failure mechanisms and switching behaviors of memory devices both in micro- and nano-scale. Microstructure and composition evolution will also be carried out so that the structure-property relationship of memory device can be understood.