自 1987 年 OLED 發展以來，OLED在固態照明及顯示器應用發展快速，在顯示器應用方面，需要有高效率、高亮度及長壽命的OLED，而串聯式OLED能夠透過串聯數個發光單元來構建高效率、高亮度、長壽命的OLED顯示器和有機固態光源。
本論文透過改變電洞傳輸層及電子傳輸層的厚度，以及發光層的比例，將綠色有機磷光元件將單一元件的效率調整至最佳，並透過電性測試最佳電荷產生層，選用CNT2T:Li2CO3/ HATCN作為電荷產生層，量測電容來找出電荷產生層達到高效的電荷產生能力，而我們研究透過電荷產生層連接兩個發光單元及三個發光單元，並與單一元件做比較。
而我們透過改變電洞傳輸層來調配出最佳光學諧振，使串聯式元件每個發光單元發揮出最佳效率，與單一元件與Two、Three – tandem效率相比較，Two-tandem、Three-tandem分別為單一元件的2.13、2.8倍，Three – tandem串聯式元件之元件表現為量子效率達到了80.60 %、電流效率為334.80 cd/A、功率效率129.81 lm/W，在操作電流0.135 mA、1000 cd/m2亮度下，元件半衰期壽命為 48136 h。

Since the development of OLEDs in 1987, OLEDs have developed rapidly in solid-state lighting and display applications. Tandem OLEDs are capable of building high-efficiency, high-brightness, long-lifetime OLED displays and organic solid-state light sources by connecting several light emitting units in series.
In this paper, by varying the thickness of the hole transmission layer and the electron transmission layer, as well as the ratio of the emitting layer. Optimize the efficiency of a single device with green organic phosphorescent device. And the best charge generation layer by electrical test. CNT2T:Li2CO3/ HATCN is selected as the charge generation layer. Measure capacitance to find the charge generation layer to achieve efficient charge generation capability. We studied the connection of two light-emitting units and three light-emitting units through charge-generating layers and compared it with a single device.
And we adjust the best optical resonance by changing the hole transmission layer, Let each light-emitting unit of the tandem element exert the best efficiency. Compared to single component and Two, Three - tandem efficiency.
Two-tandem and Three-tandem are 2.13 and 2.8 times of single device, respectively. Three - tandem device have achieved a quantum efficiency of 80.60 %, current efficiency of 334.80 cd/A, and power efficiency of 129.81 lm/W. Under the operating current of 0.135 mA and 1000 cd/A brightness, the half-lifetime of the device is 96650 h.

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