** Shares of memory chip maker Micron Technology MU.O rise 5.7% to $394.36

** Micron CFO Mark Murphy says HBM4 has entered high-volume production and shipments to customers have begun; new NAND fab on track

** "We achieved getting our HBM share close to our DRAM share in the market," Murphy said during Wolfe research conf

** Co believes margins to expand in second and third quarter

** Stock rose more than 35% in 2025

(Reporting by Kritika Lamba in Bengaluru)

((Kritika.Lamba@thomsonreuters.com))