氧化物纳米结构的自发排序
1Department of Materials and Nuclear Engineering, Department of Physics, University of Maryland, College Park, MD 20742, USA. Flat Panel Display Division, Motorola Inc., 7700 South River Parkway, Tempe, AZ 85284, USA.
Science (New York, N.Y.)
|March 24, 2000
概括
在氧化过程中,氧化物"尖端"的统一阵列自发地在薄膜上形成. 薄膜厚度和加工条件影响尖端尺寸和密度,这表明现场排放应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 纳米技术纳米技术
背景情况:
- (Pd) 薄膜在各种电子和催化应用中至关重要.
- 控制薄膜上的纳米结构形成对于先进的材料特性至关重要.
研究的目的:
- 为了研究薄膜氧化过程中纳米结构的自发形成.
- 了解薄膜特性,加工条件和纳米结构形态学的关系.
- 探索这些纳米结构的潜在应用.
主要方法:
- 具有不同厚度 (40-200 nm) 的薄膜的氧化.
- 由此产生的纳米结构 (尖端/山丘) 的表征.
- 分析薄膜厚度,颗粒度,回火和氧化条件的影响.
- 测量光电子发射特性.
主要成果:
- 均的形氧化物尖端阵列自发形成.
- 尖端高度随着薄膜厚度的增加,从0.5增加到1.2微米.
- 随着厚度的增加,尖端密度从55 x 10^6下降到12 x 10^6 cm^-2
- 在较厚的薄膜中观察到更广泛的高度分布.
结论:
- 的薄膜厚度和氧化条件决定了氧化物尖端的形成和形态.
- 观察到的尖端显示了增强的光电子发射.
- 这些氧化物尖端显示出对现场发射装置应用的希望.
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