Sun, K., Hakim, M. M. A. and Ashburn, P.
Metal Induced Lateral Crystallization of Amorphous Silicon Nanoribbons for Application in Biosensors.
At E-MRS 2009 Spring Meeting, Strasbourg, France,
08 - 12 Jun 2009.
Full text not available from this repository.
Recently, Si nanowires and micron-wide nanoribbons are gaining much attention for biosensing because they offer real-time, label-free, high sensitivity sensing. Currently Si nanowires are fabricated using CMOS technology, SOI substrates and e-beam lithography, which give high costs. In this paper we investigate a lower cost alternative using TFT technology and study the lateral crystallization of Si nanoribbons for application in Si biosensors. A comparison is made of the crystallization of a-Si on SiO2 and on air for use in top-gate and surround-gate sensors. The crystallization is assessed using Normarski microscopy, planar and cross-sectional SEM and defect etching. The results show better lateral crystallization for Si-on-Air than Si-on-Oxide. For a 10h anneal at 550°C, the crystallization extended 24um for Si-on-Air and 11um for Si-on-SiO2, whilst a 20h anneal at 525°C gives 7.7um and 4.9um respectively. Plan-view SEM images also show slightly lower NiSi2 precipitates in Si-on-Air than Si-on-Oxide. Cross-section SEM images show randomly nucleated grains at the bottom of the crystallized layer, with a density of 1.3/um and 3.2/um for Si-on-Air and Si-on-Oxide, indicating the suppression of random grain nucleation in Si-on-Air samples. These results promise better electrical performance from crystallized Si-on-Air sensors than Si-on-Oxide sensors.
Actions (login required)