氮化銦(InN)能隙為0.65 eV，在近幾年是具有潛力的三族氮化物半導體之一，擁有優越的電子傳輸特性。由於在三族氮化物中，有最低的有效質量和最高的電子遷移率，因此具有發展為高頻的光電及電子元件的潛力。
在本論文中，我們探討了利用有機金屬化學氣相沉積法(MOCVD)成長之氮化銦薄膜的載子動力學。藉由光激發-兆赫波探測技術，我們可以量到兆赫波的穿透率變化，然後用雙指數函數分析實驗曲線，我們發現樣品快速弛豫時間為13皮秒左右，推測主要可能是跟樣品表面陷阱的載子捕捉有關。慢速弛豫時間對應不同厚度分別為111、182和870皮秒，與分子束磊晶成長(MBE)之氮化銦薄膜相較，我們發現快速弛豫過程為MOCVD成長之InN載子動能弛豫的主要貢獻，而非慢速弛豫，這與MBE成長之薄膜相反。為了瞭解缺陷相關載子再結合的機制，我們也做了不同光激發強度的量測，並且透過X射線繞射儀的搖擺曲線量測，來解釋實驗結果。
經由光激發-兆赫波探測量測，我們可以更加了解InN的載子動力學。並且從分析結果我們可以得到氮化銦的弛豫時間和主要貢獻為快速弛豫過程。

Indium nitride (InN) is a group-Ⅲ nitride semiconductor with narrow direct band gap (0.65 eV), and superior electronic transport properties. With the lowest effective mass and highest mobility among other group-Ⅲ nitride, InN has potential to be used in high frequency optoelectronic devices.
In this thesis, we investigated carrier dynamics of indium nitride films grown by metal organic chemical vapor deposition. By using optical-pump terahertz-probe technique, we found that the fast relaxation time of InN thin films (200, 300, 500 nm in thickness) might be due to photocarrier capture by the surface trapping events, and the value is about 13 ps. Then we compare the experimental results for different thickness and different fabrication of previous work grown by molecular beam epitaxy. However, slow relaxation time is about few hundred ps. In order to know the mechanism of defect-related recombination process, we also do the experiment of pump fluence dependence for indium nitride films. Then using the rocking curve measurement by X-Ray Diffractometer to explain the experimental results.
Through the optical-pump terahertz-probe measurement, we can well explain the physical phenomenon of fast relaxation time and slow relaxation time for indium nitride films. In addition, from the fitting results, we can know that the value of relaxation time and fast relaxation process is the dominant for our samples.

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