鈦鉭摻雜氮化鉿在前瞻金氧半元件特性研究

Study of Ti and Ta-doped HfOxNy on Characteristics of Advanced Metal-Oxide-Semiconductor Devices

邱閔聖(Min-Sheng Chiu)

指導教授 ： 洪政豪

共同指導教授 ： 鄭錦隆(Chin-Lung Cheng)

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2008年)

https://doi.org/10.6827/NFU.2008.00024

摘要

金氧半元件二氧化矽閘介電層縮小化的目的是用來改善積體電路元件的性能，然而二氧化矽閘介電層縮小化的同時，所衍生出嚴重穿隧漏電流是一個不容忽視的問題，因為高介電係數材料在相同等效二氧化矽層厚度下具有較高之物理厚度，因此取代了二氧化矽閘介電層改善穿隧漏電流的問題。近幾年，由於氮化鉿(HfON)高介電係數材料熱穩定性佳、較廣的能隙及較大的能障等優點，因此受到注目，但由於其介電係數只有20-25，因此本論文，利用較高介電係數鈦(Ti)及鉭(Ta)摻雜氮化鉿(HfON)高介電係數材料形成複合HfTiON、HfTaON或HfTiTaON等，期能找到一最佳高介電係數材料應用於金氧半元件閘介電層。
本論文利用不同的Ta及Ti摻雜量搭配不同的後沈積熱處理(Post Deposition Annealing, PDA)來探討對MOS元件的HfON電性及可靠度影響，並藉由高溫量測獲得漏電流機制的確認。實驗發現，當氮化鉿只摻雜鈦時，HfTiON具有很低的等效氧化層厚度，但其漏電流及可靠度較差，相反的只有摻雜鉭的時候，HfTaON具有不錯的熱穩定度，但等效氧化層厚度較差，當氮化鉿摻雜適當的Ti及Ta時的HfTiTaON具有較佳的特性，包含等效氧化層厚度(EOT)、遲滯、應力引起的漏電流(SILC)、應力引起的平帶電壓偏移(SIFS)等。

關鍵字

高介電係數材料 ； 氮化鉿 ； 後沈積熱處理 ； 氮化鉿鈦鉭

並列摘要

The continuous scaling down of gate silicon dioxide thickness in metal–oxide–semiconductor (MOS) devices is achieving continued improvement in integrated circuit (IC) performance. However, the accompanying high leakage current of ultrathin silicon oxide is a significant problem for IC application. High-dielectric-constant (high-k) gate oxides with larger physical thickness while identical equivalent oxide thickness (EOT) have been widely used to supersede SiO for reducing gate leakage current in MOS devices. Recently, the HfON, which possess advantageous characteristics such as good thermal stability, wide band gaps, and large band offsets, has received much attention. However, the dielectric-constant of the HfON is not higher enough. Therefore, in this thesis, the effects of Ti and Ta-doped HfON on electrical and reliability characteristics of advanced MOS devices were investigated.
In this thesis, the Ti and Ta-doped HfON as the dielectric of advanced MOS devices were investigated. The post-deposition annealing also was adopted to demonstrate the characteristics of MOS devices. The results show that the lower EOT and poor leakage current were achieved for the MOS devices with HfTiON dielectric. On the contrary, the good thermal stability and poor EOT were achieved for the MOS devices with HfTaON dielectric. The excellent electrical and reliability characteristics can be achieved by the MOS devices with HfTiTaON doping with suitable amount of Ti and Ta.

並列關鍵字

High-k materials ； HfOxNy ； post-deposition annealing ； HfTiTaON

參考文獻

參考文獻

[1] N. Lu, H.-J. Li, M. Gardner, S. Wickramanayaka, and D.-L. Kwong, IEEE Electron Device Letters, Vol. 26, No. 5, May (2005).

[2] N. Lu, H.-J. Li, M. Gardner, and D.-L. Kwong, IEEE Electron Device Letters, Vol. 26, No. 11, November (2005).

[3] Se Jong Rhee, Feng Zhu, Hyoung-Sub Kim, Chang Hwan Choi, Chang Yong Kang, Manhong Zhang, Tackhwi Lee, Injo Ok, Siddarth A. Krishnan, and Jack C. Lee, IEEE Electron Device Letters, Vol. 27, No. 4, April (2006).

[4] Man Chang, Minseok Jo, Hokyung Park, Hyunsang Hwang, Byoung Hun Lee, and Rino Choi, IEEE Electron Device Letters, Vol. 28, No. 1, January (2007).