Toward Site-Specific Dopant Contrast in Scanning Electron Microscopy

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F14%3APU109853" target="_blank" >RIV/00216305:26620/14:PU109853 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1017/S1431927614000968" target="_blank" >http://dx.doi.org/10.1017/S1431927614000968</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1017/S1431927614000968" target="_blank" >10.1017/S1431927614000968</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Toward Site-Specific Dopant Contrast in Scanning Electron Microscopy

Popis výsledku v původním jazyce

Since semiconductor devices are being scaled down to dimensions of several nanometers there is a growing need for techniques capable of quantitative analysis of dopant concentrations at the nanometer scale in all three dimensions. Imaging dopant contrast by scanning electron microscopy (SEM) is a very promising method, but many unresolved issues hinder its routine application for device analysis, especially in cases of buried layers where site-specific sample preparation is challenging. Here, we report on optimization of site-specific sample preparation by the focused Ga ion beam (FIB) technique that provides improved dopant contrast in SEM. Similar to FIB lamella preparation for transmission electron microscopy, a polishing sequence with decreasing ion energy is necessary to minimize the thickness of the electronically dead layer. We have achieved contrast values comparable to the cleaved sample, being able to detect dopant concentrations down to 1x10^16 cm^-3. A theoretical model shows that the electronically dead layer corresponds to an amorphized Si layer formed during ion beam polishing. Our results also demonstrate that contamination issues are significantly suppressed for FIB-treated samples compared with cleaved ones.

Název v anglickém jazyce

Toward Site-Specific Dopant Contrast in Scanning Electron Microscopy

Popis výsledku anglicky

Since semiconductor devices are being scaled down to dimensions of several nanometers there is a growing need for techniques capable of quantitative analysis of dopant concentrations at the nanometer scale in all three dimensions. Imaging dopant contrast by scanning electron microscopy (SEM) is a very promising method, but many unresolved issues hinder its routine application for device analysis, especially in cases of buried layers where site-specific sample preparation is challenging. Here, we report on optimization of site-specific sample preparation by the focused Ga ion beam (FIB) technique that provides improved dopant contrast in SEM. Similar to FIB lamella preparation for transmission electron microscopy, a polishing sequence with decreasing ion energy is necessary to minimize the thickness of the electronically dead layer. We have achieved contrast values comparable to the cleaved sample, being able to detect dopant concentrations down to 1x10^16 cm^-3. A theoretical model shows that the electronically dead layer corresponds to an amorphized Si layer formed during ion beam polishing. Our results also demonstrate that contamination issues are significantly suppressed for FIB-treated samples compared with cleaved ones.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2014

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

MICROSCOPY AND MICROANALYSIS

ISSN

1431-9276

e-ISSN

1435-8115

Svazek periodika

20

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

6

Strana od-do

1312-1317

Kód UT WoS článku

000340259800038

EID výsledku v databázi Scopus

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