【作者】 孙晓娟；

【导师】 胡礼中；

【作者基本信息】 大连理工大学 ， 微电子学与固体电子学， 2007， 硕士

【摘要】 扫描近场光学显微镜（SNOM）是一种能探测纳米尺寸的新型显微工具。这种显微镜利用局限在微小孔径上的隐失场提供物体表面形貌的细节，其分辨率可突破传统光学的衍射极限。它的问世不仅会促进物理、化学、生物和材料等学科的研究与发展，还将引起信息技术和生命科学的变革。在信息技术上，SNOM最重要的潜在应用领域之一就是超高密度光信息存储。在这一应用上，一种微型单片集成式SNOM传感器已经被提出，它由PIN探测器、VCSEL和金字塔状微探尖三个单元构造而成。目前，制备具有PIN探测器的VCSEL结构在技术上已经成熟，在独立衬底上制备GaAs金字塔状微探尖也有一些方法。所以实现SNOM传感器的关键问题有两个：一是如何制备适合SNOM的高质量的微探尖，二是怎样将微探尖制作在带有PIN探测器的VCSEL上形成集成式结构。本文报道了一种简单可重复的用于制备混合集成式SNOM传感头的GaAs金字塔状微探尖的制备和转移技术。利用选择液相外延法制备GaAs微探尖，通过改变SiO₂掩膜的制备方法，提高微探尖的质量；微探尖的转移技术为：首先在GaAs衬底上用金属有机化学汽相沉积生长Al_0.7Ga_0.3As／GaAs复合外延层，形成GaAs／Al_0.7Ga_0.3As／GaAs结构；然后通过选择液相外延技术在此结构上生长GaAs微探尖；接着利用浓HCl选择腐蚀Al_0.7Ga_0.3As外延层实现微探尖的剥离；最后利用负型光刻胶将剥离下来的微探尖粘到目标片上，实现微探尖的转移。在腐蚀过程中，GaAs微探尖被埋在正型光刻胶里以抵抗损伤。利用扫描电子显微镜对转移后的微探尖进行了表征。结果表明，通过此种方法能够成功地将GaAs微探尖转移到目标晶片上，并且在转移过程中微探尖不会受到损伤。这一成果对SNOM传感头的应用迈进了重要的一步。更多还原

【Abstract】 Scanningnear-field optical microscopy （SNOM） is a novel tool for the research down tonanometer scale. It utilizes the evanescent field confined at the tiny aperture for providingimages of object surfaces with a resolution beyond the classical optical diffraction limit, andwill have great influences not only in the fields of physics, chemistry, biology and materialscience, but also in medicine and information technology. One of the most important potentialapplications may be found in ultrahigh density optical data storage. For this application, apromising architecture of monolithic integrated SNOM sensor has been proposed. This sensoris composed by a GaAs microtip, a vertical-cavity surface-emitting laser （VCSEL） cavity anda pin monitor. Up to now, the techniques for manufacturing VCSEL cavity with a PINdetector are quite mature and many techniques have also been developed to fabricate GaAsmicrotips on independent GaAs substrates. So fabricating the GaAs micrtip with better qualityand integrating the tip onto the VCSEL wafer with a pin monitor becomes the key to realizethe integrated SNOM sensor.In this paper, a simple and reproducible fabricating and transferring of GaAs microtipstechnique is presented for hybrid integrated SNOM sensor. GaAs microtips are grown usingselective liquid phase epitaxy and the tips are improved by changing the method of fabricatingSiO₂ layer. For the tips transfer technique, a GaAs/Al_0.7Ga_0.3As/GaAs sandwich structure isfirstly formed on GaAs （001） substrate by metalorganic chemical vapor deposition, and thenGaAs pyramidal microtips are grown on the sandwich structure using selective liquid-phaseepitaxy. The GaAs microtips are removed from the sandwich structure by selective wetetching Al_0.7Ga_0.3As layer using concentrated HCl solution. Finally, the tips are glued onto thetarget wafer by a negative photoresist. During this transfer process the tips are completelyencapsulated in a positive photoresist to protect against attack. Scanning electron microscopyimages show that GaAs tips can be successfully transferred without any damage by thistechnique. The achievement reported here represents a significant step towards the applicationof scanning near-field optical microscopy sensor.更多还原