本論文將著重在雙閘極金氧半場效電晶體(Dual-Gate MOSFETs)的特性分析與量測,其包括了直流量測(DC I-V)、小訊號S參數(S-parameters)、大訊號負載拉移(Load-Pull Measurement)、低頻雜訊量測(Flicker Noise)以及高頻雜訊量測(High Frequency Noise)。因雙閘極電晶體擁有兩個閘極,論文中也會將不同閘極長度(Gate Length)組合而成的電晶體做特性比較。其中本文也替雙閘極金氧半場效電晶體建立對應之模型以利預測元件特性,並將量測與模擬結果作比較驗證。最後再將雙閘極金氧半場效電晶體應用於低雜訊放大器(Low-Noise Amplifier)與壓控振盪器(Voltage-Controlled Oscillator)。The dual-gate MOSFETs having two independent gates with the same body P-well layer have been analyzed in this thesis. The characteristics including DC I-V, S-parameters, and the large-signal behavior using load-pull system were measured to realize the performance improvement. Flicker noise and high-frequency noise depending on the gate and body biases are also investigated in different gate lengths of dual-gate MOSFETs. Furthermore, a small-signal equivalent dual-gate model is established to verify the small- and large-signal characteristics of the proposed model as well. Two RF circuits, 5 GHz low-noise amplifier and 9 GHz voltage-controlled oscillator, are also designed by using the proposed large-signal model stacking two MOSFETs in cascode. The measured results show that the performances of the dual-gate circuits can be accurately predicted by employing the proposed model.