利用自我對準金屬源極與汲極於砷化銦鎵金氧半場效電晶體之電性與化性的研究

Abstract

在此篇論文中，首先我們成功的製造出鎳砷化銦鎵合金在250度1分鐘氮氣退火下。鎳砷化銦鎵合金的片電阻(sheet resistance)只有傳統N型離子佈植砷化銦鎵三分之一倍。在250度1分鐘氮氣退火下的鎳砷化銦鎵合金/砷化銦鎵二極體開關電流比有四個數量級;電子蕭特機能障(Schottky barrier for electron)為 0.16 eV。 其次，我們成功製造出鎳砷化銦鎵的蕭特機N型金氧半電晶體於磷化銦上;而此電晶體的開關比為8.1103，次臨界擺幅為191 mV/dec，源極汲極電阻(RSD)為11 km。最大的電子遷移率可以達到1138 cm2/V-s。我們比較了電導法(conductance method)與全電導法(full conductance method)之間的差異。而我們採用全電導法所取出來的表面缺陷密度(interface states density)約為11012 cm-2eV-1 位於價帶高0.6電子伏特的能階處。接著我們使用CP測量(charge pumping measurement)去萃取邊緣缺陷密度(border trap density)，其邊緣缺陷密度為1019 到 1020 cm-3eV-1 在位於三氧化二鋁(Al2O3)的導帶下方1.3 eV至1.65 eV，其萃取缺陷深度距離表面約16 Å至22 Å處。其邊緣缺陷密度也會對次臨界擺幅有極大影響。 最後，我們成功製造出鎳砷化銦鎵的蕭特機N型金氧半電晶體於矽基板上。此元件展現出極大的驅動電流，約85 A/m在驅動電壓為1.6伏特及汲極電壓為2伏特下，然而此電晶體有較大的漏電流相較於N型金氧半電晶體於磷化銦基板上，其原因可能來自於通道缺陷。

In this thesis, we successfully fabricated nickel indium gallium arsenide alloy by post metal annealing (PMA) at 250 C in N2 for 1 min. Moreover, the sheet resistance of Ni-InGaAs was lower than InGaAs doped with n-type. The Shottcky barrier height for electron was about 0.16 eV and the on/off ratio of Shottcky junction was about 1.1104. Secondly, InGaAs NMOSFETs on InP substrate with self-aligned nickel S/D was manufactured successfully. The on/off ratio was about 8.1103, the subthreshold swing was around 191 mV/dec, and the low source/drain resistance of 11 km were achieved. The peak mobility was about 1138 cm2/V-s. Moreover, we discussed the difference between the conductance method and the full-conductance method. The Dit extracted by the full-conductance method was about 11012 cm-2eV-1 at ET = EV + 0.6 eV. By charge pumping extraction, the border trap density was around 1019 to 1020 cm-3eV-1 situated at ET - EC  -1.3 eV to -1.65 eV and the depth of border trap was from 16 Å to 22 Å. Border traps had large impact on subthreshold swing. Finally, InGaAs NMOSFETs on Si substrate with self-aligned nickel S/D was fabricated successfully. A high drive-current of 85 A/m at VG-VT = 1.6 V and VD = 2 V was achieved. However, the NMOSFETs demonstrated larger leakage current than InGaAs NMOSFETs on InP substrate that might be due to the defects of channel layer.