本論文研究以銻砷化銦鎵做為應力減緩層，對砷化銦量子點產生的影響。藉由光致發光實驗我們觀察到覆蓋銻砷化銦鎵應力減緩層的量子點發光波長會隨銦及銻成分的增加產生紅移，但超過其成分限制時會導致發光效率變差。此外，低溫光致發光量測結果顯示，應力減緩層中加入銻後，銻能提升能帶，導帶能障差異(ΔEc)因此提高，降低載子在高溫時獲得能量進行熱逃逸的機率，顯著提升了發光效率。

接下來我們嘗試將銻加入量子點內，形成銻砷化銦量子點，但由於晶格常數變大，使量子點頂部所受應力增加，形成凹陷，且銻的表面活性化效應造成量子點高度下降，使發光波長產生藍移。因此改用生長完量子點後濺撒銻的方式，做砷跟銻的置換，結果顯示不但能保持量子點原本的型態，還能利用銻砷化銦能隙較小的特性，使波長紅移到1405 nm。

最後，為了能將量子點實際應用到VCSEL元件中，我們製作PIN二極體，驗證其電流特性，並生長符合本實驗量子點波段範圍的DBR結構，未來能夠以此基礎在量子點上下生長DBR並製作完整的VCSEL元件。

In this work, we investigate the effects of using InGaAsSb as a strain reducing layer for InAs quantum dots. Photoluminescence measurements reveal that the emission wavelength of quantum dots covered with an InGaAsSb strain reducing layer red-shifts as the indium and antimony compositions increase. However, their emission efficiency degrades when the compositions exceed a certain limit. Furthermore, low-temperature photoluminescence measurements show that the incorporation of antimony into the strain reducing layer raises the conduction band, increases the conduction band offset (ΔEc), and therefore reduces the probability of carrier escape at elevated temperatures, significantly enhancing emission intensity.

Next, we attempted to incorporate antimony into the quantum dots to form InAsSb quantum dots. However, the larger lattice constant of InAsSb increased the strain at the top of the quantum dots, causing the collapse of top of the quantum dots. Additionally, the surfactant effect of the antimony reduced the height of the quantum dots, causing a blueshift in emission wavelength. As an alternative, we employed a post-growth antimony soaking process to facilitate the exchange arsenic atoms with antimony atoms. This approach not only preserved the original shape of the quantum dots but also extended the emission wavelength to 1405 nm due to the narrower bandgap of InAsSb.

In this study, we fabricated PIN diodes with the InAsSb QDs as the active region. A distributed Bragg reflector (DBR) structure that matches the wavelength range of the quantum dots was also prepared. In the future, these foundations can be used to realize electrically pumped 1.4 m QD vertical cavity surface emitting lasers (VCSELs).

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