軟性崩潰對深次微米 n 型通道金氧半電晶體特性

Abstract

在本論文中，我們主要著重於軟性崩潰對n型深次微米金氧半電晶體特性所造成衝擊之研究。在研究中, 發現崩潰點所處相對位置會影響元件之特性，尤其對於元件崩潰劣化後之電流切換特性造成決定性影響。當崩潰發生在通道上方之閘極氧化層內，電晶體導通狀態下閘極電流之特性並無明顯變化，而此現象正與崩潰點位於汲極上方氧化層內所造成元件特性劣化形成強烈對比。再者，通道崩潰後，電晶體操作於關閉狀態區內，且閘極電壓在小於 –1.5 V之情況下，我們證實了兩個寄生雙載子接面電晶體亦相對操作於主動區內，進而造成汲, 閘極等電流的明顯上升。

The impacts of soft-breakdown (SBD) on the characteristics of deep sub-micron NMOSFETs were investigated. It is shown that the BD location plays a crucial role in the post-BD switching function of the device. When BD occurs at the channel, the turn-on behavior of the drain current would not be significantly affected, which is in strong contrast to the case of BD at the drain. Nevertheless, significant increase in gate and drain currents is observed in the off-state when the gate voltage is more negative then –1.5 V. Its origin is identified to be due to the action of two parasitic bipolar transistors formed after the occurrence of SBD at the channel.