Exhibit 99.1 News Release Axcelis Announces Financial Results for First Quarter 2024 Revenue, Gross Margin and EPS Beat Guidance BEVERLY, Mass. — May 1, 2024—Axcelis Technologies, Inc. (Nasdaq: ACLS) today announced financial results for the first quarter ended March 31, 2024. The Company reported first quarter revenue of $252.4 million, compared to$310.3 million for the fourth quarter of 2023. Gross margin for the quarter was 46%, compared to 44.4% in the fourth quarter. Operating profit for the quarter w ...