本論文著重於全新單片集成發光高電子遷移率電晶體(light emitting high electron mobility transistor, LEHEMT)結構之研究，在汲極端加入MBE成長之20 nm高濃度摻雜N+氮化鎵，與P型氮化鎵形成穿隧接面(tunneling junction)，作為P型歐姆接觸。
穿隧接面發光高電子遷移率電晶體(tunneling junction LEHEMT, TJ-LEHEMT)於本實驗中成功開發，汲極端接觸電阻(contact resistance, Rc)較一般鎳/金(Ni/Au)之P型歐姆接觸降低約兩個數量級，閾值電壓(threshold voltage, Vth)為-1.58V，最大轉移電導值(transconductance, Gm)為50.82mS/mm，導通電阻(specific on-state resistance, Ron,sp)為4.02mΩ-cm2，飽和電流於閘極電壓(Vg)為1 V時可達228.85 mA/mm，並且擁有良好的發光特性，於Vg為3V、汲極電壓(Vd)為15V時，發出波長為366.96 nm之紫外光，半高寬(full width at half maximum, FWHM)為10.34 nm，同時可透過Vg及Vd有效地控制發光強度。
同時，成功製作增強型高電子遷移率電晶體(enhancement mode HEMT, E-mode HEMT)，Vth較空乏型HEMT(depletion mode HEMT, D-mode HEMT)增加2 V，達到0.41 V，作為未來矩陣化之控制電晶體參考。

This thesis is focused on study of a novel light emitting high electron mobility transistor (LEHEMT) structure which applies 20 nm heavily doped MBE regrown N+ GaN to the drain side, in which N+ GaN and P-type GaN forms a tunneling junction that acts as P-type ohmic contact in the LEHEMT.
Tunneling junction high electron mobility transistor (TJ-LEHEMT) was successfully fabricated with a contact resistance (Rc) lowered by two orders of magnitude in comparison with a conventional Ni/Au P-type ohmic contact. The measured threshold voltage (Vth), peak transconductance (Gm) and specific on-state resistance (Ron,sp) are -1.58 V, 50.82 mS/mm, 4.02 mΩ-cm2 respectively. The maximum saturation current is 228.85 mA/mm at Vg=1 V. Outstanding optical characteristics were obtained with a light peak wavelength 366.96 nm in the UV range and FWHM(full width at half maximum) was 10.34 nm at Vg= 3 V, Vd= 15 V. Good controllability of light intensity with Vg and Vd were confirmed.
At the same time, enhancement mode HEMT (E-mode HEMT) was successfully fabricated with Vth= 0.41 V, which is 2 V greater than that of the depletion mode HEMT (D-mode HEMT). The E-mode HEMT is desired as the controlling transistor reference in active matrix LED driver.

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