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Title: Designing high performance precursors for atomic layer deposition of silicon oxide

Abstract

Conformal and continuous silicon oxide films produced by atomic layer deposition (ALD) are enabling novel processing schemes and integrated device structures. The increasing drive toward lower temperature processing requires new precursors with even higher reactivity. The aminosilane family of precursors has advantages due to their reactive nature and relative ease of use. In this paper, the authors present the experimental results that reveal the uniqueness of the monoaminosilane structure [(R{sub 2}N)SiH{sub 3}] in providing ultralow temperature silicon oxide depositions. Disubstituted aminosilanes with primary amines such as in bis(t-butylamino)silane and with secondary amines such as in bis(diethylamino)silane were compared with a representative monoaminosilane: di-sec-butylaminosilane (DSBAS). DSBAS showed the highest growth per cycle in both thermal and plasma enhanced ALD. These findings show the importance of the arrangement of the precursor's organic groups in an ALD silicon oxide process.

Authors:
; ; ; ; ; ;  [1];  [2];  [3]
  1. Air Products and Chemicals, Inc., 1969 Palomar Oaks Way, Carlsbad, California 92011 (United States)
  2. Air Products and Chemicals, Inc., 7201 Hamilton Blvd., Allentown, Pennsylvania 18195 (United States)
  3. Air Products and Chemicals, Inc., 2 Dongsanhuan North Road, Chaoyang District, Beijing 100027 (China)
Publication Date:
OSTI Identifier:
22392110
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 33; Journal Issue: 1; Other Information: (c) 2014 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; AMINES; DESIGN; FILMS; PERFORMANCE; PLASMA; PRECURSOR; PROCESSING; SILANES; SILICON OXIDES

Citation Formats

Mallikarjunan, Anupama, E-mail: mallika@airproducts.com, Chandra, Haripin, Xiao, Manchao, Lei, Xinjian, Pearlstein, Ronald M., Bowen, Heather R., O'Neill, Mark L., Derecskei-Kovacs, Agnes, and Han, Bing. Designing high performance precursors for atomic layer deposition of silicon oxide. United States: N. p., 2015. Web. doi:10.1116/1.4903275.
Mallikarjunan, Anupama, E-mail: mallika@airproducts.com, Chandra, Haripin, Xiao, Manchao, Lei, Xinjian, Pearlstein, Ronald M., Bowen, Heather R., O'Neill, Mark L., Derecskei-Kovacs, Agnes, & Han, Bing. Designing high performance precursors for atomic layer deposition of silicon oxide. United States. doi:10.1116/1.4903275.
Mallikarjunan, Anupama, E-mail: mallika@airproducts.com, Chandra, Haripin, Xiao, Manchao, Lei, Xinjian, Pearlstein, Ronald M., Bowen, Heather R., O'Neill, Mark L., Derecskei-Kovacs, Agnes, and Han, Bing. 2015. "Designing high performance precursors for atomic layer deposition of silicon oxide". United States. doi:10.1116/1.4903275.
@article{osti_22392110,
title = {Designing high performance precursors for atomic layer deposition of silicon oxide},
author = {Mallikarjunan, Anupama, E-mail: mallika@airproducts.com and Chandra, Haripin and Xiao, Manchao and Lei, Xinjian and Pearlstein, Ronald M. and Bowen, Heather R. and O'Neill, Mark L. and Derecskei-Kovacs, Agnes and Han, Bing},
abstractNote = {Conformal and continuous silicon oxide films produced by atomic layer deposition (ALD) are enabling novel processing schemes and integrated device structures. The increasing drive toward lower temperature processing requires new precursors with even higher reactivity. The aminosilane family of precursors has advantages due to their reactive nature and relative ease of use. In this paper, the authors present the experimental results that reveal the uniqueness of the monoaminosilane structure [(R{sub 2}N)SiH{sub 3}] in providing ultralow temperature silicon oxide depositions. Disubstituted aminosilanes with primary amines such as in bis(t-butylamino)silane and with secondary amines such as in bis(diethylamino)silane were compared with a representative monoaminosilane: di-sec-butylaminosilane (DSBAS). DSBAS showed the highest growth per cycle in both thermal and plasma enhanced ALD. These findings show the importance of the arrangement of the precursor's organic groups in an ALD silicon oxide process.},
doi = {10.1116/1.4903275},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 1,
volume = 33,
place = {United States},
year = 2015,
month = 1
}
  • The thermal surface chemistry of copper(I)-N,N′-di-sec-butylacetamidinate, [Cu({sup s}Bu-amd)]{sub 2}, a metalorganic complex recently proposed for the chemical-based deposition of copper films, has been characterized on SiO{sub 2} films under ultrahigh vacuum conditions by x-ray photoelectron spectroscopy (XPS). Initial adsorption at cryogenic temperatures results in the oxidation of the copper centers with Cu 2p{sub 3/2} XPS binding energies close to those seen for a +2 oxidation state, an observation that the authors interpret as the result of the additional coordination of oxygen atoms from the surface to the Cu atoms of the molecular acetamidinate dimer. Either heating to 300 K or dosingmore » the precursor directly at that temperature leads to the loss of one of its two ligands, presumably via hydrogenation/protonation with a hydrogen/proton from a silanol group, or following a similar reaction on a defect site. By approximately 500 K the Cu 2p{sub 3/2}, C 1s, and N 1s XPS data suggest that the remaining acetamidinate ligand is displaced from the copper center and bonds to the silicon oxide directly, after which temperatures above 900 K need to be reached to promote further (and only partial) decomposition of those organic moieties. It was also shown that the uptake of the Cu precursor is self-limiting at either 300 or 500 K, although the initial chemistry is somewhat different at the two temperatures, and that the nature of the substrate also defines reactivity, with the thin native silicon oxide layer always present on Si(100) surfaces being less reactive than thicker films grown by evaporation, presumably because of the lower density of surface nucleation sites.« less
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