SAN FRANCISCO — Memory chip makers are expected to shell out about $26 billion on flash memory capex in 2019, a decline of about 18% from an estimated $31.9 billion last year, according to market research firm IC Insights.

Despite a decline in spending as the expansion of capacity for 3D NAND takes a breather, flash is expected to lead all other semiconductor sectors in capital spending en route to a third consecutive year north of $25 billion, the firm said.

Flash memory spending trailed foundry spending in 2016. But flash capex jumped by 92% in 2017 to reach $27.6 billion, IC Insights said.

Samsung, the leader in flash memory, spent about $9 billion on flash capex in 2018, down from about $13 billion in 2017, according to IC Insights. The total was still good enough to account for about 28% of the industry's total of flash capex, the firm added. IC Insights forecasts that Samsung's flash capex will further decline to about $7 billion this year.

According to IC Insights, Samsung and fellow flash stalwarts Micron Technology, SK Hynix and Toshiba Memory will continue spending heavily on flash capex in an effort to stay ahead of upstart Chinese vendors gearing up to enter the 3D NAND market.

Last year, XMC/Yangtze River Storage Technology (YMTC), which is owned by Tsinghua Unigroup, completed construction of its new fab, installed equipment, and began small-volume production of 32-layer 3D NAND flash, IC Insights said.