Energy deposition during molecular depth profiling experiments with cluster ion beams.

Energy deposition during molecular depth profiling experiments with cluster ion beams. Research Abstract Details 

Research Abstract Table of Contents

Jump to the:

Energy deposition during molecular depth profiling experiments with cluster ion beams. Abstract Text:

The role of the location of energy deposition during cluster ion bombardment on the quality of molecular depth profiling was examined by varying the incident angle geometry. Cholesterol films approximately 300 nm in thickness deposited onto silicon substrates were eroded using 40-keV C60(+) at incident angles ranging from 5 degrees to 73 degrees with respect to the surface normal. The erosion process was evaluated by determining at each incident angle the total sputtering yield of cholesterol molecules, the damage cross section of the cholesterol molecules, the altered layer thickness within the solid, the sputter yield decay in the quasi-steady-state sputter regime, and the interface width between the cholesterol film and the silicon substrate. The results show that the total sputtering yield is largest relative to the product of the damage cross section and the altered layer thickness at 73 degrees incidence, suggesting that the amount of chemical damage accumulated is least when glancing incident geometries are used. Moreover, the signal decay in the quasi-steady-state sputter regime is observed to be smallest at off-normal and glancing incident geometries. To elucidate the signal decay at near-normal incidence, an extension to an erosion model is introduced in which a fluence-dependent decay in sputter yield is incorporated for the quasi-steady-state regime. Last, interface width calculations indicate that at glancing incidence the damaged depth within the solid is smallest. Collectively, the measurements suggest that decreased chemical damage is not necessarily dependent upon an increased sputter yield or a decreased damage cross section but instead dependent upon depositing the incident energy nearer the solid surface resulting in a smaller altered layer thickness. Hence, glancing incident angles are best suited for maintaining chemical information during molecular depth profiling using 40-keV C60(+).

Energy deposition during molecular depth profiling experiments with cluster ion beams. Publishing Authors By Initials

For similar abstracts research abstracts see: abstracts research

PUBMED ID PMID:

MEDLINE DATE:

Energy deposition during molecular depth profiling experiments with cluster ion beams. Journal Published:

PUBLICATION TYPE: Research Support, U.S. Gov't,

Journal: Analytical chemistry

VOLUME: 80

Page Numbers: 5293-301

Journal Abbreviation: Anal. Chem.

ISSN: 1520-6882

DAY: 13

MONTH: 06

YEAR: 2008

Energy deposition during molecular depth profiling experiments with cluster ion beams. Information

Number of References:

LANGUAGE: eng

NlmUniqueID: 370536

Energy deposition during molecular depth profiling experiments with cluster ion beams. Keywords Mesh Terms:

KEYWORDS:

MESH TERMS:

Chemical & Substance for Abstract: Energy deposition during molecular depth profiling experiments with cluster ion beams. Information

Substance Name:

Registry Number:

Grant and Affiliation Information for Energy deposition during molecular depth profiling experiments with cluster ion beams.

AFFILIATION: Department of Chemistry, Penn State University, 104 Chemistry Building, University Park, Pennsylvania 16802, USA.

Country: United States

AGENCY: United States NIBIB

GRANT: EB002016-13

ACRONYM: EB

MEDLINETA: Anal Chem

REFSOURCE:

DATABASENAME:

ACCESSION NUMBER:

Number Hits: 0

Energy deposition during molecular depth profiling experiments with cluster ion beams Related Publications

• A functional approach to stroke management in elderly patients.
• Assessment of depression in geriatric medical outpatients: the validity of two screening measures.
• Depth resolution during c60(+) profiling of multilayer molecular films.
• Diagnosis of an unusual tumor in the duodenum.
• Direct comparison of Au(3)(+) and C(60)(+) cluster projectiles in SIMS molecular depth profiling.
• Elaboration and distinctiveness in memory for faces.
• Energy deposition during molecular depth profiling experiments with cluster ion beams.
• Expanded access to rehabilitation services for older people. An urgent need.
• Fecal incontinence in an elderly man. Stanford University geriatrics case conference.
• Geriatric consultation: a functional approach.
• Implementing geriatric curricula.
• Medicare reimbursement for geriatric assessment: report of the American Geriatrics Society Ad Hoc Committee on Geriatrics Assessment.
• Mental status tests and the capacity for self-care.
• Phosphatidylethanolamine-induced cholesterol domains chemically identified with mass spectrometric imaging.
• Protocols for three-dimensional molecular imaging using mass spectrometry.
• Public financing of Medicare.
• Sphingomyelin/phosphatidylcholine and cholesterol interactions studied by imaging mass spectrometry.
• Targeting strategies: an overview of criteria and outcomes.
• Value of magnifying chromoendoscopy and narrow band imaging (NBI) in classifying colorectal polyps: a prospective controlled study.
• Working group recommendations: targeting criteria for geriatric evaluation and management research.