- 學位論文
pHEMTs小訊號和雜訊模型與其元件尺寸關係
Small signal and noise model with scaling effect of pHEMTs
摘要
隨著科技的發展與微波技術日趨重要，Ⅲ-Ⅴ族半導體中是一個很重要的元件，主要應用在軍事、衛星和商業通訊的毫米波和微波頻率上，對砷化鎵假形高電子遷移率電晶體(pHEMT)在主動元件的需求越來越高；在設計微波積體電路時，一個準確的電晶體模型，能精確的提供電路設計者元件的各種特性，是達成設計電路成功很重要的一環。 本論文包含了砷化鎵假形高電子遷移率電晶體的小訊號和小訊號雜訊模型萃取技術。利用Yang-Long直流、Cold-FET高頻量測方法，萃取電晶體外部寄生元件參數，再經由矩陣轉換求得內部本質元件參數，進而建立電晶體小訊號等效模型。再者利用雜訊相關矩陣技術，來萃取雜訊係數，建立小訊號雜訊等效電路模型。用此方法可以建立準確的小訊號雜訊模型。最後討論雜訊模型中，雜訊係數與元件尺寸關係，發現尺寸關係對小訊號雜訊係數影響極小，幾乎不會變化，除了係數P有極小的誤差。
並列摘要
GaAs pHEMT device is one of the most important semiconductor devices for military and commercial communication applications at millimeter-wave frequencies. It is very important to set up an accurately model which contains the high frequency and noise characteristics. It is helpful to design a MMIC circuit composed of these transistors. This thesis contains both the small-signal and noise modeling methods of GaAs pHEMTs. Utilizing Yang-Long DC measurement and Cold-FET high frequency measurement method, extrinsic parameters of device can be extracted. And then using matrix operation method to obtain intrinsic parameters of the device, and set up the small-signal equivalent model of the transistor. Moreover, we use the noise correlation matrix method to extract noise coefficients of intrinsic noise sources. The equivalent noise model of the device with divinable noise characteristics can be established. This model can fit well to the measured data, including high frequency and noise characteristics. Finally, we discuss the scaling effect of the noise coefficients of intrinsic noise sources. The influence of the scaling effect on the noise coefficients is unobvious. Only the parameter P has the small deviation between the different sizes at the same current density.