在本論文中，我們利用「金屬有機氣象磊晶(MOVPE)」成長新穎的氮砷化銦鎵(InGaAsN)材料當作高載子移動率電晶體(HEMTs)的通道層。在砷化鎵中摻雜適量的銦與適量的氮可以使氮砷化絪鎵晶格匹配於砷化鎵上以減少由於晶格不匹配產生的缺陷。此外，氮砷化銦鎵具有較窄的能隙與較大的導帶位移量(△Ec)導致有較佳的載子侷限能力。這些優點使得氮砷化銦鎵在高載子移動率電晶體的線性度改良上是個絕佳的選擇。

　　本論文第一部份我們研究傳統砷化銦鎵/砷化鋁鎵高載子電晶體不同厚度非摻雜砷化鋁鎵蕭特基層與其元件載子分佈的關係。運用T-CAD軟體模擬能帶結構與載子分佈並且實驗上使用CV量測取得實際上的載子分布。最後我們討論不同厚度非摻雜砷化鋁鎵蕭特基層對電特性與元件的效能的影響。

　　第二部份，運用快速回火處理來改善氮砷化銦鎵高載子移動率電晶體的效能。經過快速回火處理可以有效的改善氮砷化銦鎵的材料品質、閘極蕭特基特性以及增加通道內的載子濃度進而提升增益(Gm)與較大的閘極工作電壓擺福(GVS)。

　　最後，我們比較氮砷化銦鎵高載子移動率電晶體與傳統砷化銦鎵高載子移動率電晶體兩者之間閘極工作電壓擺福表現。使用氮砷化銦鎵當作高載子移動率電晶體的通道層取代傳統砷化銦鎵材料是因為氮砷化銦鎵具有較大的導帶位移量因此有較佳的載子侷限能力。這樣的特性提升元件線性度的表現因此可以達到較廣的閘極工作電壓擺福。此外，提升氮砷化銦鎵高載子移動率電晶體中砷化鋁鎵載子提供層的矽摻雜可以得到較大的閘極電壓擺福但犧牲了電晶體增益特性。在我們的實驗結果中，室溫下閘極尺寸為2×125μm2時氮砷化銦鎵高載子移動率電晶體的閘極工作電壓擺幅可以成功的達到7.9伏特，這樣明顯的改善在元件線性度的應用上有很好的潛力。

　In this thesis, we utilized the novel InGaAsN material as channel layer of High Electron Mobility Transistors (HEMTs) grown by Metal Organic Vapor Phase Epitaxy (MOVPE). Incorporating proper amount of indium and nitrogen into GaAs and then InGaAsN can be lattice-matched on GaAs substrate to reduce the defects induced from the dislocation due to lattice mismatch. In addition, InGaAsN has narrower bandgap and larger conduction band offset which lead to better carrier confinement. These advantages make InGaAsN as an excellent candidate to improve linearity performance in HEMTs.

　In the first part, we investigated the relationship between the carrier distributions and the conventional AlGaAs/InGaAs HEMT with different thickness of un-doped AlGaAs schottky layers. We used T-CAD software to simulate band-gap structure and carrier distribution and applied capacitance–voltage (C-V) measurement to obtain the real carrier distribution. Finally, we discussed the electrical characteristics and device performance of different AlGaAs schottky layer thickness.

　In the second part, rapid thermal annealing treatment was applied to improve the performance of InGaAsN HEMTs. RTA treatment can effectively improve InGaAsN material quality, gate schottky characteristics and increase carrier concentration in channel layer to obtain higher gm and broad gate voltage swing.

　Finally, we compared the Gate Voltage Swing (GVS) of InGaAsN HEMTs with that of conventional InGaAs HEMTs. InGaAsN is utilized as channel layer in HEMT structures to replace InGaAs material because of larger △Ec and thus has better carrier confinement, which is suitable for linear improvement to achieve broad constant transconductance regions. In addition, increasing si doping density in AlGaAs carrier supplying layer in InGaAsN HEMTs can increase carrier concentration in channel layer to obtain broad gate voltage swing but sacrifice the transconductance performance. In our experimental result, the gate voltage swing of InGaAsN HEMTs can be 7.9V successfully with a gate geometry 2×125μm2 at room temperature. The significantly improved characteristics in this work process a great potential in linear application.

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