有機薄膜電晶體是相當新穎的電子元件。它具有低溫製程及低成本的優點，並可應用在塑膠或其他可撓式基版。但有機材料應用在半導體元件上的缺點為載子遷移率低，影響開關特性。

有機薄膜電晶體在應用方面，可能會面臨與其他元件的整合而受到各種不同的工作環境影響。本論文著重於化學溶液以及溫度改變對有機薄膜電晶體特性的影響，希望能夠了解元件操作在不同工作環境下的狀況，以及元件能夠容忍的最大限度。

第一個部份的實驗，是有關化學溶液對元件的特性影響探討，由於異丙醇與丙酮是最常使用在清潔步驟中的溶液，因此選用這兩種溶液。異丙醇及丙酮在短時間內就造成元件特性大幅衰減，包括最大飽和電流、載子遷移率、開關電流比等，都有顯著的退化現象，因此證實異丙醇與丙酮的確對於元件具有很大的破壞性，進而了解有機薄膜電晶體並不適合在具有化學溶液的環境中做元件之整合。

第二部份的實驗，是探討溫度改變，對於有機薄膜電晶體的操作及特性影響，發現不同厚度的元件當加熱到80℃時，載子遷移率皆達到最大，繼續加熱到140℃後特性衰減。另外，隨著溫度的升高，會造成臨界電壓往正向偏移。這個實驗探討了加熱對於有機薄膜電晶體的特性有ㄧ定的影響及趨勢，並且會改變有機材料表面特性。因次在應用上必須注意臨界電壓改變以及載子遷移率的變化。

綜合上述的實驗，外在的環境改變，如化學溶液、溫度改變，都會對有機薄膜電晶體造成顯著的特性改變，未來在整合應用上可能需要進ㄧ步的封裝以或改良來達到最佳的工作環境。

Organic thin film transistors are novel electronic devices. The unique advantages of these devices include low process temperature, low cost, and the flexibility of selecting various substrates that are available. However, the carrier mobility of organic material is still relatively poor when it is used as semiconductor because of the limit in their switching speed.

OTFT may integrate with other devices for many potential applications, but then the devices may inevitably face the problem of operating in different working environments. This thesis will focus on the effect of chemical solution and temperature change on OTFT devices in order to explore the operation limit and different environmental situation.

The first part is concerned with the chemical solution effect on OTFT devices. The devices are immersed in isopropyl alcohol and acetone, which are often used to clean the substrate for different period of time. The device characteristics deteriorate dramatically in short time, specifically the reduction in maximum saturation current, carrier mobility, on/off current ratio often observed. This experiment shows that using aforementioned chemical solutions is not a good choice involving the integration of OTFTs with other prospective devices.

The second part is dedicated to examining the effect of temperature change on OTFT performance. When heating the devices to 80℃, the mobility of devices with different active layer thickness ultimately reaches a largest value, but then once the temperature is increased up to 140℃, the mobility decreases. In addition, threshold voltage of all devices shifts in the direction of positive VG axis. In fact, the temperature can be a sensitive parameter that effect the property of active layer surface and changes the device characteristics of OTFT.

In conclusion, the chemical solution and temperature change may influence the performance of OTFT devices. To prevent the possible damages due to the process-induced effects during the device integration and possible severe operating environments for OTFTs, effective package procedures must be implemented to alleviate the side effects of process involved in device fabrication.

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