Thickness determination of ultrathin oxide films and its application in magnetic tunnel junctions

J. Joshua Yang; Chengxiang Ji; Ying Yang; Y. Austin Chang; Feng X. Liu; Bharat B. Pant; Allan E. Schultz

doi:10.1007/s11664-006-0324-5

Thickness determination of ultrathin oxide films and its application in magnetic tunnel junctions

J. Joshua Yang, Chengxiang Ji, Ying Yang, Y. Austin Chang, Feng X. Liu, Bharat B. Pant, Allan E. Schultz

Research output: Contribution to journal › Article › peer-review

2 Scopus citations

Abstract

In this study we propose a method for utilizing x-ray photoelectron spectroscopy (XPS), a surface sensitive technique, coupled with a wedge-shaped sample to determine the thickness of an ultrathin aluminum oxide tunnel barrier layer (∼2 nm) in a magnetic tunnel junction (MTJ), The uncertainty of the measured thickness is analyzed and the factors affecting the accuracy of this measurement are discussed as well as the advantages over the use of high-resolution transmission electron microscopy. Using this approach, we were able to quickly optimize the thickness of an aluminum oxide layer in a fabricated MTJ, yielding a high magnetoresistance ratio. In addition to XPS, one can also use Auger electron spectroscopy to determine the thickness of the oxidized tunnel barrier layer. This method can also be applied to other tunnel barrier materials such as the nitrides.

Original language	English
Pages (from-to)	2142-2146
Number of pages	5
Journal	Journal of Electronic Materials
Volume	35
Issue number	12
DOIs	https://doi.org/10.1007/s11664-006-0324-5
State	Published - Dec 2006
Externally published	Yes

Funding

This work is supported by a grant from the Division of Materials Science, Office of Basic Energy Research of the Department of Energy Grant No. DE-FG02-99ER45777, Seagate Technology, and the Wisconsin Distinguished Professorship.

Funders	Funder number
U.S. Department of Energy	DE-FG02-99ER45777
Division of Materials Sciences and Engineering
Seagate Technology

Keywords

Magnetic tunnel junction
Oxide
X-ray photoelectron spectroscopy (XPS)

Access to Document

10.1007/s11664-006-0324-5

Cite this

@article{0600b1d42c264423bff14c938141cf69,

title = "Thickness determination of ultrathin oxide films and its application in magnetic tunnel junctions",

abstract = "In this study we propose a method for utilizing x-ray photoelectron spectroscopy (XPS), a surface sensitive technique, coupled with a wedge-shaped sample to determine the thickness of an ultrathin aluminum oxide tunnel barrier layer (∼2 nm) in a magnetic tunnel junction (MTJ), The uncertainty of the measured thickness is analyzed and the factors affecting the accuracy of this measurement are discussed as well as the advantages over the use of high-resolution transmission electron microscopy. Using this approach, we were able to quickly optimize the thickness of an aluminum oxide layer in a fabricated MTJ, yielding a high magnetoresistance ratio. In addition to XPS, one can also use Auger electron spectroscopy to determine the thickness of the oxidized tunnel barrier layer. This method can also be applied to other tunnel barrier materials such as the nitrides.",

keywords = "Magnetic tunnel junction, Oxide, X-ray photoelectron spectroscopy (XPS)",

author = "Yang, {J. Joshua} and Chengxiang Ji and Ying Yang and Chang, {Y. Austin} and Liu, {Feng X.} and Pant, {Bharat B.} and Schultz, {Allan E.}",

year = "2006",

month = dec,

doi = "10.1007/s11664-006-0324-5",

language = "English",

volume = "35",

pages = "2142--2146",

journal = "Journal of Electronic Materials",

issn = "0361-5235",

number = "12",

}

TY - JOUR

T1 - Thickness determination of ultrathin oxide films and its application in magnetic tunnel junctions

AU - Yang, J. Joshua

AU - Ji, Chengxiang

AU - Yang, Ying

AU - Chang, Y. Austin

AU - Liu, Feng X.

AU - Pant, Bharat B.

AU - Schultz, Allan E.

PY - 2006/12

Y1 - 2006/12

N2 - In this study we propose a method for utilizing x-ray photoelectron spectroscopy (XPS), a surface sensitive technique, coupled with a wedge-shaped sample to determine the thickness of an ultrathin aluminum oxide tunnel barrier layer (∼2 nm) in a magnetic tunnel junction (MTJ), The uncertainty of the measured thickness is analyzed and the factors affecting the accuracy of this measurement are discussed as well as the advantages over the use of high-resolution transmission electron microscopy. Using this approach, we were able to quickly optimize the thickness of an aluminum oxide layer in a fabricated MTJ, yielding a high magnetoresistance ratio. In addition to XPS, one can also use Auger electron spectroscopy to determine the thickness of the oxidized tunnel barrier layer. This method can also be applied to other tunnel barrier materials such as the nitrides.

AB - In this study we propose a method for utilizing x-ray photoelectron spectroscopy (XPS), a surface sensitive technique, coupled with a wedge-shaped sample to determine the thickness of an ultrathin aluminum oxide tunnel barrier layer (∼2 nm) in a magnetic tunnel junction (MTJ), The uncertainty of the measured thickness is analyzed and the factors affecting the accuracy of this measurement are discussed as well as the advantages over the use of high-resolution transmission electron microscopy. Using this approach, we were able to quickly optimize the thickness of an aluminum oxide layer in a fabricated MTJ, yielding a high magnetoresistance ratio. In addition to XPS, one can also use Auger electron spectroscopy to determine the thickness of the oxidized tunnel barrier layer. This method can also be applied to other tunnel barrier materials such as the nitrides.

KW - Magnetic tunnel junction

KW - Oxide

KW - X-ray photoelectron spectroscopy (XPS)

UR - http://www.scopus.com/inward/record.url?scp=33846411831&partnerID=8YFLogxK

U2 - 10.1007/s11664-006-0324-5

DO - 10.1007/s11664-006-0324-5

M3 - Article

AN - SCOPUS:33846411831

SN - 0361-5235

VL - 35

SP - 2142

EP - 2146

JO - Journal of Electronic Materials

JF - Journal of Electronic Materials

IS - 12

ER -

Thickness determination of ultrathin oxide films and its application in magnetic tunnel junctions

Abstract

Funding

Keywords

Access to Document

Other files and links

Fingerprint

Cite this