High-Throughput Area-Selective Spatial Atomic Layer Deposition of SiO2 with Interleaved Small Molecule Inhibitors and Integrated Back-Etch Correction for Low Defectivity

High-Throughput Area-Selective Spatial Atomic Layer Deposition of SiO2 with Interleaved Small Molecule Inhibitors and Integrated Back-Etch Correction for Low Defectivity

Karasulu,
Mameli, A.
Roozeboom, F.

2023

A first-of-its-kind area-selective deposition process for SiO2 is developed consisting of film deposition with interleaved exposures to small molecule inhibitors (SMIs) and back-etch correction steps, within the same spatial atomic layer deposition (ALD) tool. The synergy of these aspects results in selective SiO2 deposition up to ˜23 nm with high selectivity and throughput, with SiO2 growth area and ZnO nongrowth area. The selectivity is corroborated by both X-ray photoelectron spectroscopy (XPS) and low-energy ion scattering spectroscopy (LEIS). The selectivity conferred by two different SMIs, ethylbutyric acid, and pivalic acid has been compared experimentally and theoretically. Density Functional Theory (DFT) calculations reveal that selective surface functionalization using both SMIs is predominantly controlled thermodynamically, while the better selectivity achieved when using trimethylacetic acid can be explained by its higher packing density compared to ethylbutyric acid. By employing the trimethylacetic acid as SMI on other starting surfaces (Ta2O5, ZrO2, etc.) and probing the selectivity, a broader use of carboxylic acid inhibitors for different substrates is demonstrated. It is believed that the current results highlight the subtleties in SMI properties such as size, geometry, and packing, as well as interleaved back-etch steps, which are key in developing ever more effective strategies for highly selective deposition processes.

Area-selective atomic layer deposition
ALD
Atomic-level computational modeling
Sensity functional theory
DFT
Low energy ion scattering spectroscopy
LEIS
SiO2
Spatial atomic layer deposition
High Tech Systems & Materials
Industrial Innovation

http://resolver.tudelft.nl/uuid:5c9f5927-025d-4ae5-b2dc-763acd68402d

https://doi.org/10.1002/adma.202301204

986469

Wiley

0935-9648

Advanced Materials

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