Prior to his public service, Dr. Appelbaum gained more than thirty years of deep expertise in the semiconductor industry. He spent twenty-two years at KLA, a leading global technology company, where he held several senior executive positions, including Senior Corporate Vice President and President of KLA-Israel (1995 – 2017). Before joining KLA, he was the CEO of a Gallium Arsenide Diode startup in Migdal HaEmek, Israel. Additionally, Dr. Appelbaum served as Vice President of Operations and Director of Program Management at SCD, a joint venture between El-Op and Rafael in Israel. He worked as an R&D Manager at Rockwell International Corporation in Dallas, Texas, and Newbury Park, California, for four years (1987-1991). Early in his career, he was a postdoctoral researcher and Member of Technical Staff (MTS) at AT&T Bell Labs in Murray Hill, New Jersey, for four years (1983 – 1987).
在从事公共服务之前，Appelbaum博士已在半导体行业积累了30多年深厚经验。他在全球领先科技公司科磊（KLA）工作了22年，期间担任多个高级管理职务，包括高级企业副总裁及KLA以色列公司总裁（1995—2017年）。加入KLA之前，他曾担任以色列米格达勒哈埃梅克一家砷化镓二极管初创企业的首席执行官。此外，Appelbaum博士还曾担任以色列SCD公司的运营副总裁兼项目管理总监。SCD是以色列El-Op公司与拉斐尔先进防务系统公司（Rafael）成立的合资企业。
1987年至1991年间，他曾在美国德克萨斯州达拉斯和加利福尼亚州纽伯里帕克的罗克韦尔国际公司（Rockwell International Corporation）担任研发经理。在职业生涯早期，他曾于1983年至1987年在美国新泽西州默里山的AT&T贝尔实验室担任博士后研究员及技术人员（Member of Technical Staff，MTS）。