具有基板散熱金屬結構之氮化銦鋁/氮化鋁/氮化鎵/矽金屬-氧化物-半導體異質結構場效電晶體之研製

Abstract

中文摘要 本專題研究以超音波霧化熱裂解沉積技術成長以氧化鋁為氧化層的氮化銦鋁/氮化鋁/氮化鎵異質結構形成金屬-氧化物-半導體場效電晶體，且在基板底部研製3-μm深金屬溝槽結構，並藉由在矽（Si）基板底部的金屬溝槽上塗有150-nm厚的鎳（Ni）金屬層，可改善元件散熱效率。由於利用超音波霧化熱裂解沉積高介電常數氧化鋁當閘極介電層，因而增強閘極絕緣能力與表面鈍化效果，進而有效地降低閘極漏電流。 經由製程最佳化條件下之氧化鋁閘極介電層氮化銦鋁/氮化鋁/氮化鎵之金屬-氧化物-半導體場效電晶體（傳統蕭特基閘極電晶體）改善了最大電流密度IDS，max 為1.08（0.86）A / mm，閘極偏壓擺幅GVS為4（2）V，開/關電流比（Ion/Ioff）為8.9 × 108（7.4 × 104），次臨界擺幅為140（244）mV / dec，兩端關閉狀態閘極-汲極崩潰電壓（BVGD）為-191.1（-173.8）V，導通電壓（Von）為4.2（1.2）V，三端導通狀態汲極-源極崩潰電壓（BVDS）為155.9（98.5）V。提高了功率性能，也包括飽和輸出功率（Pout）為27.9（21.5）dBm，功率增益（Ga）為20.3（15.5）dB，功率附加效率（P.A.E）為44.3％（34.8％）。

Abstract This thesis studies new Al2O3 dielectric In0.18Al0.82N/AlN/GaN metal oxide semiconductor heterostructure field effect transistors (MOS-HFETs) with backside metal trench structure grown by using a non-vacuum ultrasonic spray pyrolysis deposition technique. The depth of metal trenches was 3-μm and coated with 150-nm thick Ni were formed on the backside of the substrate to improve the heat dissipation efficiency. As compare with Schottky-gate HFET, the present In0.18Al0.82N/AlN/GaN MOS-HFET was illustrated improved maximum drain source current density of 0.86 (1.08) A/mm at VDS = 8 V, gate voltage swing of 2 (4) V, on/off current ratio of 7.4 × 104 (8.9 × 108) , subthreshold swing of 244 (140) mV/dec, two-terminal off-state gate drain breakdown voltage of −173.8 (−191.1) V, turn-on voltage of 1.2 (4.2) V, and three-terminal on-state drain source breakdown voltage of 98.5 (155.9) V. Enhanced power performances, including saturated output power of 21.5 (27.9) dBm, power gain of 15.5 (20.3) dB, and power added efficiency (P.A.E) of 34.8% (44.3%) are reached.