Atomera Inc (ATOM)

[roadkilll]

Why a Soitec link? Nov 2023 Whitepaper
Using wafers from Soitec, Atomera has been able to demonstrate the unique dopant retention of
MST on ultra-thinned RF-SOI substrates. Regular RF-SOI (high resistivity, trap-rich) substrates
were thinned to 120A silicon on BOX thickness, and then blanket MST layers plus a 30nm capping
silicon layer were grown. After growth, and during regular device fabrication, the wafers were
implanted with boron. The as-implanted boron profile is quite broad as shown in the white open
circles in Figure 10. The MST oxygen layers then trap diffusing boron to create the steep profiles
as shown in blue (after RTA anneal) and red (after full thermal Dt of the RF-SOI manufacturing
process). Compared to the SSRW profile formed by selective epitaxial growth on the boron-doped
.
MST® for PMIC and RF-SOI Switches
Copyright © 2022-2023 Atomera Incorporated p. 10
SOI structure in Figure 9, MST enables greater than a10x steeper SSRW profile by implanting
boron into the SOI substrate after blanket MST epi growth.
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Summary
MST provides doping engineering and mobility enhancement, enabling the further scaling of key
semiconductor switch devices. MSTcad is a silicon verified tool for Sentaurus users, which helps
optimize the integration of MST. We have used MSTcad to engineer MST-SP, an industry-leading
5V switch for PMIC applications. MSTcad is actively in use to improve higher voltage and RF-
SOI devices, and there are many further applications of the technology.