Conformality Measurement Needs and Challenges

Survey among ALD professionals

Mikko Utriainen, Riikka L. Puurunen

Research output: Contribution to conferenceConference AbstractScientificpeer-review

Abstract

Conformality is a core value proposition of Atomic Layer Deposition (ALD) and related thin film processing methods. However, conformality is challenging to measure and quantify and standardized methods do not exist either. This study focuses to identify specific needs and problems in the conformality measurements. The method was a survey and questionnaire. Responders were ALD or other thin film R&D and process engineering experts (N=45), representing academic (N=24) and industry (N=21) and geographically 55% Europe, 25% North America, 20% unknown. All responders considered that it is important or very important to measure conformality, however, only 38% were satisfied with their present measurement methodology. The dominant method is SEM/TEM analysis from microscopic vertical trenches or other high aspect ratio structures. Only few uses alternative approaches (e.g. macroscopic lateral stacks or indirect methods) and those more frequently in academy than in industry. Some responders also state that they try to avoid conformality measurements. Survey showed that the most important attribute was the reliability and accuracy (98% responded 4-5, in the range 1-5) followed by availability of test structures (87%). Lowest success in the present methodology was the speed of measurement (84% responded 1-3, in the range 1-5), followed by cost (71%) and availability of test structures (67%). Responders also described their main challenges. Slow speed is due to tedious (cross-sectional) sample preparation, inaccurate dimensional analyses and multiple sample fractions. Test structures should be comparable to dimensions of real substrates, provide variable 3D dimensions and be available at low cost. Avoidance of breaking valuable wafers was also mentioned. Alternative self-made stacks have challenges e.g. in processing condition compatibility. Other accuracy challenges were low film thickness, inadequate resolution in SEM and missing surface area factor. Responses also pointed out the need of mapping the details on the trench wall/ 3D surface, like morphology, composition, evolution of the film and properties of the film. Significant gap between high importance and low satisfaction of the current measurement approaches leads to conclude that there is a strong need among professionals to get improvements. In this respect, new innovations or joint activities in standardization can support the whole ALD community.
Original languageEnglish
Publication statusPublished - 30 Jul 2018
MoE publication typeNot Eligible
Event18th International Conference on Atomic Layer Deposition, ALD/ALE 2018: Featuring the 5th International Atomic Layer Etching Workshop - Songdo Convensia in Incheon, Incheon, Korea, Republic of
Duration: 29 Jul 20181 Aug 2018
https://ald2018.avs.org/

Conference

Conference18th International Conference on Atomic Layer Deposition, ALD/ALE 2018
Abbreviated titleALD/ALE 2018
CountryKorea, Republic of
CityIncheon
Period29/07/181/08/18
Internet address

Fingerprint

films (materials)
methodology
industry
processing technology
standardization
questionnaires
testing
sampling

Keywords

  • PillarHall
  • ALD
  • conformality
  • LHAR

Cite this

Utriainen, M., & Puurunen, R. L. (2018). Conformality Measurement Needs and Challenges: Survey among ALD professionals. Abstract from 18th International Conference on Atomic Layer Deposition, ALD/ALE 2018, Incheon, Korea, Republic of.
Utriainen, Mikko ; Puurunen, Riikka L. / Conformality Measurement Needs and Challenges : Survey among ALD professionals. Abstract from 18th International Conference on Atomic Layer Deposition, ALD/ALE 2018, Incheon, Korea, Republic of.
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Utriainen, M & Puurunen, RL 2018, 'Conformality Measurement Needs and Challenges: Survey among ALD professionals' 18th International Conference on Atomic Layer Deposition, ALD/ALE 2018, Incheon, Korea, Republic of, 29/07/18 - 1/08/18, .

Conformality Measurement Needs and Challenges : Survey among ALD professionals. / Utriainen, Mikko; Puurunen, Riikka L.

2018. Abstract from 18th International Conference on Atomic Layer Deposition, ALD/ALE 2018, Incheon, Korea, Republic of.

Research output: Contribution to conferenceConference AbstractScientificpeer-review

TY - CONF

T1 - Conformality Measurement Needs and Challenges

T2 - Survey among ALD professionals

AU - Utriainen, Mikko

AU - Puurunen, Riikka L.

N1 - Poster

PY - 2018/7/30

Y1 - 2018/7/30

N2 - Conformality is a core value proposition of Atomic Layer Deposition (ALD) and related thin film processing methods. However, conformality is challenging to measure and quantify and standardized methods do not exist either. This study focuses to identify specific needs and problems in the conformality measurements. The method was a survey and questionnaire. Responders were ALD or other thin film R&D and process engineering experts (N=45), representing academic (N=24) and industry (N=21) and geographically 55% Europe, 25% North America, 20% unknown. All responders considered that it is important or very important to measure conformality, however, only 38% were satisfied with their present measurement methodology. The dominant method is SEM/TEM analysis from microscopic vertical trenches or other high aspect ratio structures. Only few uses alternative approaches (e.g. macroscopic lateral stacks or indirect methods) and those more frequently in academy than in industry. Some responders also state that they try to avoid conformality measurements. Survey showed that the most important attribute was the reliability and accuracy (98% responded 4-5, in the range 1-5) followed by availability of test structures (87%). Lowest success in the present methodology was the speed of measurement (84% responded 1-3, in the range 1-5), followed by cost (71%) and availability of test structures (67%). Responders also described their main challenges. Slow speed is due to tedious (cross-sectional) sample preparation, inaccurate dimensional analyses and multiple sample fractions. Test structures should be comparable to dimensions of real substrates, provide variable 3D dimensions and be available at low cost. Avoidance of breaking valuable wafers was also mentioned. Alternative self-made stacks have challenges e.g. in processing condition compatibility. Other accuracy challenges were low film thickness, inadequate resolution in SEM and missing surface area factor. Responses also pointed out the need of mapping the details on the trench wall/ 3D surface, like morphology, composition, evolution of the film and properties of the film. Significant gap between high importance and low satisfaction of the current measurement approaches leads to conclude that there is a strong need among professionals to get improvements. In this respect, new innovations or joint activities in standardization can support the whole ALD community.

AB - Conformality is a core value proposition of Atomic Layer Deposition (ALD) and related thin film processing methods. However, conformality is challenging to measure and quantify and standardized methods do not exist either. This study focuses to identify specific needs and problems in the conformality measurements. The method was a survey and questionnaire. Responders were ALD or other thin film R&D and process engineering experts (N=45), representing academic (N=24) and industry (N=21) and geographically 55% Europe, 25% North America, 20% unknown. All responders considered that it is important or very important to measure conformality, however, only 38% were satisfied with their present measurement methodology. The dominant method is SEM/TEM analysis from microscopic vertical trenches or other high aspect ratio structures. Only few uses alternative approaches (e.g. macroscopic lateral stacks or indirect methods) and those more frequently in academy than in industry. Some responders also state that they try to avoid conformality measurements. Survey showed that the most important attribute was the reliability and accuracy (98% responded 4-5, in the range 1-5) followed by availability of test structures (87%). Lowest success in the present methodology was the speed of measurement (84% responded 1-3, in the range 1-5), followed by cost (71%) and availability of test structures (67%). Responders also described their main challenges. Slow speed is due to tedious (cross-sectional) sample preparation, inaccurate dimensional analyses and multiple sample fractions. Test structures should be comparable to dimensions of real substrates, provide variable 3D dimensions and be available at low cost. Avoidance of breaking valuable wafers was also mentioned. Alternative self-made stacks have challenges e.g. in processing condition compatibility. Other accuracy challenges were low film thickness, inadequate resolution in SEM and missing surface area factor. Responses also pointed out the need of mapping the details on the trench wall/ 3D surface, like morphology, composition, evolution of the film and properties of the film. Significant gap between high importance and low satisfaction of the current measurement approaches leads to conclude that there is a strong need among professionals to get improvements. In this respect, new innovations or joint activities in standardization can support the whole ALD community.

KW - PillarHall

KW - ALD

KW - conformality

KW - LHAR

M3 - Conference Abstract

ER -

Utriainen M, Puurunen RL. Conformality Measurement Needs and Challenges: Survey among ALD professionals. 2018. Abstract from 18th International Conference on Atomic Layer Deposition, ALD/ALE 2018, Incheon, Korea, Republic of.