Exhibit 16.1
November 12, 2019
Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549
Commissioners:
We have read the statements made by Onto Innovation Inc., formerly known as Nanometrics Incorporated (“Onto Innovation”) (copy attached), which we understand will be filed with the Securities and Exchange Commission, pursuant to Item 4.01 of Form 8-K of Onto Innovation, dated November 11, 2019. We agree with the statements concerning our Firm contained therein.
Very truly yours,
/s/PricewaterhouseCoopers LLP
San Jose, California
Attachment