Low temperature process for strontium bismuth tantalate thin films
Low temperature process for strontium bismuth tantalate thin films
复制标题
钽酸锶铋薄膜的低温工艺
DOI：
10.1080/10584580008222247
复制
发表时间：
2000
影响因子：
0.7
通讯作者：
C. A. Paz de Araújo
中科院分区：
文献类型：
--
作者：
J. Celinska;V. Joshi;S. Narayan;L. Mcmillan;C. A. Paz de Araújo
摘要 随着 CMOS 尺寸的缩小，处理总热预算的限制也随之缩小。对于 0.18 μm 设计规则，结深度和自对准多晶硅化物工艺要求将最高处理温度限制在 700°C 以下，最好低至 650°C。对于 FeRAM，这会导致铁电薄膜结晶可用的热预算受到限制。 SBT和SBTN薄膜通常在700°C或更高温度下退火。将结晶温度降低至650°C需要抑制萤石相以获得良好的铁电性能。我们开发了一种基于 CSD 的 SBT 薄膜低温工艺，可产生优异的铁电性能。几种材料和工艺参数已经被优化以抑制萤石相。这些包括薄膜化学计量和厚度、退火环境和升温速率、紫外线能量和前体溶剂。在本文中，我们提出了 SBT 薄膜的完整 650°C 工艺，重点介绍了工艺修改及其对铁电性能的影响。
Abstract As CMOS dimensions shrink so does the limitation on total thermal budget for processing. For 0.18 μm design rules, the junction depth and the salicide process requirements limit the maximum processing temperature to below 700°C, preferably down to 650°C. For FeRAMs, this results in limitation on the thermal budget available for the crystallization of ferroelectric films. SBT and SBTN films have been generally annealed at 700°C or higher. Lowering the crystallization temperature down to 650°C requires the suppression of fluorite phase in order to obtain good ferroelectric performance. We have developed a CSD based low temperature process for SBT films yielding excellent ferroelectric properties. Several materials and process parameters have been optimized to suppress the fluorite phase. These include film stoichiometry and thickness, anneal ambient and ramp rates, UV energy and precursor solvents. In this paper we present a complete 650°C process for SBT thin films, highlighting process modifications and their effect on ferroelectric performance.