電化學原子層沉積製備Ag和Ag(Cu)薄膜之特性研究

Preparation of Ag andAg(Cu) Thin Film by Electrochemical Atomic Layer Deposition

黃家宏(Jia-Hong Hung)

指導教授 ： 方昭訓

國立虎尾科技大學/工程學院/材料科學與工程系材料科學與綠色能源工程碩士班/碩士(2016年)

摘要

近年來因單位面積中的元件數目持續增加，過多的連接使RC延遲日益嚴重，也導致元件效能無法再明顯突破。包含銅導線尺寸縮小，其電阻率會因為表面散射、晶界散射和界面粗糙的緣故而增加，故許多研究嘗試使用更低電阻之材料取而代之。銀導線雖然有電阻較低之優勢，相對也有著穩定性和附著性不好的狀況，為改善Ag導線之缺點，本研究將利用電化學原子層沉積 (EC-ALD) 技術製備銀銅合金，並進行分析探討其沉積特性。
實驗在Si (100) 上利用磁控濺鍍沉積10 nm釕薄膜，且藉由循環伏安法(CV) 以電位掃描方式去除釕薄膜的表面氧化物，在釕基板上優先沉積銅膜，再利用鉛和銀、銅之活性差(氧化電位差)，以-520 mV 60s低電位沉積一鉛層將其當作犧牲層。然後在OCP狀態分別加入銀離子和銅離子溶液置換60s，再以銀銅層數比調控其比例。另一項實驗在OCP狀態加入銀銅混和溶液使兩金屬同步置換，並依離子濃度的比例進行調控。上述兩方式方別沉積可得銀銅合金薄膜，再以SEM、X光繞射分析儀、四點探針、X射線光電子能譜學分析薄膜特性。

關鍵字

電化學原子層沉積 ； 欠電位沉積 ； 表面侷限氧化還原反應 ； 銀 & 銀銅薄膜

並列摘要

Due to the increase in the edvice density recentry, lead to increase in RC delay. when the device size is down. Silver has shown a reduced electrical resistance but suffer from stability and adhesion. In this report, we used Electrochemical Atomic Layer Deposition (EC-ALD) technology to prepare the Ag and Ag(Cu) films.
The Si (100) wafer was coated with 10 nm Ru by sputter, and that was cleamed by cyclic voltammetry (CV) at a scan rate of 5 mV/s. The first Underpotential deposition (UPD) Cu-layer was deposited on the Ru substrate. Pb was choosed as a sacrificial layer on the Cu/Ru/Si substrate and then Cu sol. and Ag sol was flushed into cell at OCP 60s that Pb was exchanged Ag and Cu atom by Surface limited redox replacement (SLRR) . Another mix solution of (Ag + Cu) was flushed into cell at OCP for 60 s that Pb was exchanged for Ag & Cu atom by SLRR. Ag-Cu film was formed by repeated process for 48 cycles. The resulting Ag(Cu) films were characterized using X-ray diffraction, electrochemical chromatograpHy and four point probe, Scanning electron microscope and X-ray Photoelectron Spectrometer.

並列關鍵字

Electrochemical atomic layer deposition ； underpotential deposition ； Surface limited redox replacement ； Ag(Cu) thin films

參考文獻

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