鈣鈦礦量子點由於其光學特性容易由成分和製程調整，也有很高的發光量子產率(Photo-Luminescence Quantum Yield, PLQY)，再加上製作方法簡單，故近年來鈣鈦礦量子點在半導體材料中極為流行，希望能發展為下一代顯示器的材料。然而其穩定性不佳，在大氣環境中，受到光照或是在較潮溼的環境下，鈣鈦礦量子點容易被破壞。
由於鈣鈦礦量子點為立方體結構，相對於傳統型量子點為近乎圓形結構，在表面分析上掌握度較高，能有很明顯的形貌區分。
本論文是希望藉由AFM掃描分散的量子點的高度來決定尺寸，再由共軛焦顯微鏡(confocal microscope)取得單顆量子點的螢光光譜和空間分布影像，以研究鈣鈦礦量子點的量子侷限效應。

The changes in size of quantum dots cause shifts of energy states. Also, the band gap between the valence band and the conduction band will be different. When the size of the quantum dot is smaller than de Broglie wavelength or Bohr radius, quantum confinement effect will become obvious.
Perovskite quantum dots (PQD) become very popular among semiconductor materials in recently years due to a few reasons. First, PQD have very high fluorescence quantum yield. Second, it is easy to tune optical properties through different compositions and reaction time. Third, the fabrication process is easy in usual laboratories. However, PQD are unstable in the ambient, humid environment or under light illumination. This is the major issue to be solved in PQD research.
Since PQD have cubic lattices, their appearances are quite distinct from the traditional quantum dots. It is easy to identify their heights and shapes by an atomic force microscope (AFM).
This thesis aims at investigating the quantum confinement effect of PQD. We first determining the size (height) of PQD by an AFM. Then we obtain the fluorescence mapping and spectrum of individual PQD. By analyzing the spectral shifts versus the size of each PQD, the quantum confinement effect is presented in results.

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