ACLS · Annual Report (Form 10-K) · Filed February 26, 2026

Axcelis Technologies Inc — 10-K exhibit

acls-20251231xex21d1.htm

Axcelis Technologies Inc on Boardroom Alpha

Exhibit 21.1

Axcelis Technologies, Inc.

Exhibit 21.1 to Form 10-K for the year ended December 31, 2025

Subsidiaries

The following is a list of all direct and indirect wholly-owned subsidiaries of Axcelis Technologies, Inc. as of the date hereof:

Domestic Subsidiaries

1.Axcelis Technologies (Israel) Inc., a Delaware corporation

2.Victory Merger Sub, Inc., a Delaware corporation

European Subsidiaries

2.	Axcelis Technologies GmbH (Germany)

3.	Axcelis Technologies, Srl (Italy)

4.	Axcelis Technologies, Sarl (France)

Asian Subsidiaries

5.	Axcelis Technologies, KK (Japan)

6.	Axcelis Technologies Limited (Korea)

7.	Axcelis Technologies, Ltd. (Taiwan)

8.	Axcelis Technologies Pte. Ltd. (Singapore)

9.	Axcelis Technologies Semiconductor Trading (Shanghai) Co., Ltd. (Peoples Republic of China)

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