在近幾年來，低溫複晶矽薄膜電晶體，由於其優異的元件特性已經廣泛應用於小型至中型的顯示面板。低溫複晶矽薄膜技術逐漸克服遷移率的問題並提供互補式電路技術，在元件縮小化、面板開口率、功率消耗、畫面品質與解析度上有絕對的優勢。將驅動電路整合於玻璃上，使面板同時具有窄框化(Narrow Frame Size)與高畫質的特性。因此，低溫複晶矽面板是未來的小尺寸顯示裝置的主流。
　　低溫複晶矽的生命週期是面板技術發的重要關鍵之一，面板的可靠度關係著系統面板的效能，由於周邊驅動電路控制高壓訊號，長期操作於高電壓或高電流的環境，電晶體可靠度的要求更加重要。然而畫素與整合電路的尺寸不斷縮小，將面臨到諸如熱載子效應(Hot Carrier Effect)、自發熱效應(Self-Heating Effect)等可靠度問題。
　　本研究將討論低溫複晶矽薄膜電晶體在交流訊號操作下的劣化行為，且針對操作在不同溫度、頻率、Duty cycle的情況下，所導致不同的劣化特性，進而分析低溫複晶矽驅動電路的可靠度評估方法修正。

In the last few years Low temperature polycrystalline silicon thin-film transistors, due to it's excellent device characteristics has been widely used in small-to-medium display panel. Recent years, Low temperature polycrystalline silicon thin-film transistors with high carrier mobilities allows for the realization of complementary circuit technology. As device miniaturized, panel aperture ratio, power consumption, the quality and resolution can be further improved. Integrating the driving circuits on the glass, so that the panel also has a narrow frame with higher imaging characteristics. Therefore, low-temperature polycrystalline silicon becomes the mainstream technology for small-to-medium size displays.
The reliability of the panel between the performance of the system panel, peripheral drive circuit is critical to the LTPS technology , Long-term operation in the environment of high voltage or high current ,can greatly affected the transistor’s stability. As the size of transistor is shrinking , devices will experience ever more severe hot carrier effects (Hot Carrier Effect), self-heating effects (Self-Heating Effect) leading to even worse reliability.
This study investigates the degradation behavior of the low temperature polycrystalline silicon thin-film transistors when operate in AC pulse signal. Devices stressed under different temperature, frequency, Duty cycle resulting in different deteriorating characteristics are discussed and analyzed comprehensively.

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