Plasma Enhanced Chemical Vapor Deposition of BaTiO3

BaTiO_3等钙钛矿作为薄膜铁电材料在微电子和光子学中的应用受到材料加工和兼容性问题的限制。高质量的铁电薄膜并不是在与标准硅或砷化镓工艺兼容的温度下生长的。考虑到这些材料优异的电学和光学性能，以及它们在生产低成本DRAM和非易失性存储器件方面的潜力，开发能够在低温下生产高质量铁电薄膜的新的薄膜沉积技术尤为重要。利用最近在大气压下开发的金属有机化学气相沉积(MOCVD)高温超导体沉积技术，提出了一种在与硅工艺兼容的温度下沉积BaTiO_3的等离子体增强MOCVD新工艺。第一阶段计划的具体目标是通过等离子体增强MOCVD在低于650oC的温度下在Si(100)上沉积a轴取向的BaTi03薄膜。基于BaTiO3铁电电容存储单元的原型随机存取存储器件将在第二阶段制造和测试。目标是寿命超过1012次写/读/反转访问和一年以上的断电存储，这是对最先进的铁电存储单元的重大改进。

The use of perovskites such as BaTiO3 as thin film ferroelectric materials in microelectronics and photonics has been limited by materials processing and compatibility problems. High quality ferroelectric thin films have not been grown at temperatures compatible with stand Si or GaAs processing technology. Considering the superb electrical and optical properties of these materials as well as their potential for use in the production of low cost DRAMs and non-volatile memory devices, the development of new thin film deposition techniques capable of producing high quality ferroelectric thin films at low temperatures is especially important. Utilizing techniques recently developed at ATM for the deposition of high temperature superconductors by metalorganic chemical vapor deposition (MOCVD), a novel plasma- enhanced MOCVD process for the deposition of BaTiO3 at temperatures compatible with silicon processing is proposed. The specific goal of the Phase I program is to deposit a-axis oriented BaTi03 thin films on Si(100) at temperatures below 650oC by plasma enhanced MOCVD. Prototype random access memory devices based on BaTiO3 ferroelectric capacitor storage cells will be fabricated and tested in Phase II. Lifetimes in excess of 1012 write/read/invert accesses and power-off memory retention over one year, which represent a significant improvement over state- of-the-art ferroelectric memory cells, are targeted.