** Shares of semiconductor equipment maker Onto Innovation ONTO.N rise 2.9% to $133.89 premarket

** Jefferies upgrades stock to "buy" from "hold"; raises PT to $170 from $100, now implying an over 31% increase to co's last close

** Brokerage expects co will regain lost share in Chip-on-Wafer-on-Substrate (CoWoS) semiconductor packaging technology, as co's tool nears completion

** Revenue growth can re-accelerate in second half of 2026 as new tools and underexposure to China could add to recent improvement in wafer fab equipment demand - Jefferies

** Says acquisition of Semi Lab can be accretive and could bring in $130 mln in revenue; sees could potentially benefit from semiconductor supply chains moving back to the U.S.

** 6 of 9 brokerages rate the stock "buy" or higher, three "hold" ; median PT is $147.5- data compiled by LSEG

** Up to last close, stock down nearly 22% YTD

(Reporting by Avinash P in Bengaluru)

((Avinash.P@thomsonreuters.com;))