The effects of process condition of top-TiN and TaN thickness on the effective work function of MOSCAP with high-k/metal gate stacks

Abstract： We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN and PVD-process top-TiN capping provide smaller effective work function （EW...

Full description

Saved in:
Bibliographic Details
Published inJournal of semiconductors Vol. 35; no. 10; pp. 187 - 189
Main Author 马雪丽 杨红 王文武 殷华湘 朱慧珑 赵超 陈大鹏 叶甜春
Format Journal Article
LanguageEnglish
Published 01.10.2014
Subjects
Aluminum
Capping
Diffusion
Gates
Intermetallics
Semiconductors
Stacks
TaN
TiAl基
TiN
Work functions
功函数
厚度
堆叠
工艺条件
金属栅极
Online AccessGet full text
ISSN1674-4926
DOI10.1088/1674-4926/35/10/106002

Cover

More Information
Summary:Abstract： We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN and PVD-process top-TiN capping provide smaller effective work function （EWF）, and a thicker TaN and ALD-process top-TiN capping provides a larger EWF; here, the EWF shifts are from 4.25 to 4.56 eV. A physical understanding of the dependence of the EWF on the top-TiN technology process and TaN thickness is proposed. Compared with PVD-TiN room temperature process, the ALD-TiN 400 ℃ process provides more thermal budget. It would also promote more Al atoms to diffuse into the top-TiN rather than the bottom-TiN. Meanwhile, the thicker TaN prevents the Al atoms diffusing into the bottom-TiN. These facts induce the EWF to increase.
Bibliography:Ma Xueli,Yang Hong,Wang Wenwu, Yin Huaxiang,Zhu Huilong, Zhao Chao,Chen Dapeng,Ye Tianchun（ Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China）
Abstract： We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN and PVD-process top-TiN capping provide smaller effective work function （EWF）, and a thicker TaN and ALD-process top-TiN capping provides a larger EWF; here, the EWF shifts are from 4.25 to 4.56 eV. A physical understanding of the dependence of the EWF on the top-TiN technology process and TaN thickness is proposed. Compared with PVD-TiN room temperature process, the ALD-TiN 400 ℃ process provides more thermal budget. It would also promote more Al atoms to diffuse into the top-TiN rather than the bottom-TiN. Meanwhile, the thicker TaN prevents the Al atoms diffusing into the bottom-TiN. These facts induce the EWF to increase.
11-5781/TN
TaN; ALD-TiN; PVD-TiN; effective work function
ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:1674-4926
DOI:10.1088/1674-4926/35/10/106002