同時觀察、操縱與測量奈米結構電子元件的電性與物理性質

Abstract

我們將延續先前的成功經驗，繼續專注於奈米線與量子點等奈米材料的磁性與電性方面的研究工作。繼續使用磁性量測儀器來瞭解逆磁的半導體材料在做成量子點後，為何產生順磁。此外，我們將嘗試瞭解Mn磁性雜質加入半導體量子點後，是否影響軌道電子順磁現象。在Co-ZnO奈米線研究方面，我們將朝製造室溫鐵磁半導體奈米線方向前進，並製作自旋電子元件與奈米電子元件。至於奈米線的電性方面，考量到所有半導體電子元件皆使用兩點電性量測，將探索兩點測量所須遭遇的接點問題，並仔細研究奈米接觸結的物理機制。量子點成長方向，我們除控制量子點二維成長外，並將在兩電極間製作奈米等級寬的電流導管，來研究量子傳輸現象。 除了繼續先前研究工作外，我們建議組裝一套『奈米世界探測系統』。此系統可細分為：四點量測系統、奈米尺度機械手臂與掃瞄器模組。藉由這套系統，我們將有四個點的電性探測功能，以掃瞄電子顯微鏡電子束為第五點的探針，可激發奈米結構內電子氣的能態。除此之外，奈米尺度機械手臂將為第六點探針，可外加電場做局域性電性量測，並可碰觸與操縱奈米結構。藉由高空間解析度的掃瞄器模組，我們可以讓探針接觸導電奈米結構的表面，並直接取得奈米結構表面原子結構與電子像，且可達搬運單顆量子點功能。由這套『奈米世界探測系統』，我們可以達到同時取得掃瞄電子顯微鏡影像、四點電性量測與操縱奈米結構等功能。

We will keep going with our previous research experiences to learn electricity and magnetism in nanostructures. We plan to understand orbital susceptibilities in PbSe and CdSe quantum dots and to examine the Mn-ion effects on orbital susceptibilities. We suggest to search room-temperature ferromagnetic Co-ZnO nanowires, and to fabricate spintronic and nanoelectronic devices. We will concentrate on making two-point contact devices so physics of nanocontact junctions can be explored in detail. At the same time, we will continue studying the growth of quantum-dot thin film and depositing quantum dots in the gap between the two paired electrodes. Besides maintaining our previous research work, we suggest to set up a nano-world probing system. We will install an in-situ four-point probe system in a scanning electron microscope (SEM) chamber and an electrical property probing system outside the chamber. By means of the in-situ probe system, we can monitor (by using an SEM) and measure electrical properties of nanoelectronic devices, simultaneously. The SEM e-beam serves as the fifth probe since e-beam can excite electron gas in the nanostructures. A commercial nano-scale manipulator will be installed in the second year of this project. We plan to use it as the sixth probe. The sixth probe can provide electric field to adsorb and drop nanostructures. It can also move the nanostructures mechanically. The absolute resolution of a tip against substrate surface can achieve ~100 nm that will be examined in our laboratory. We plan to make a scanner module attached on the manipulator with high special resolution. Electronic controllers, computer interfaces, and programs will be carried out by our selves. The scanner module helps to improve the special resolution. In addition, we can use it to see surface atomic structure of nanostructures and to manipulate single quantum dots. By using the nano-world probing system, we can take SEM images, measure four-probe electricity, and manipulate nanostructures at the same time.