Photoresist solvent crunch

A shortage of two obscure solvents in Japan is threatening the chemicals chipmakers use to print and package advanced memory chips. Japanese suppliers began warning Samsung Electronics and SK hynix this week that deliveries of photoresist-related materials could be disrupted. (thelec.net) The solvents are propylene glycol methyl ether and propylene glycol methyl ether acetate, known as PGME and PGMEA. They are used in photoresist, thinner, bottom anti-reflective coatings, spin-on hardmask and temporary bonding adhesives used across semiconductor production, including high-bandwidth memory. (thelec.net, shinetsu.co.jp, evgroup.com) Photoresist is the light-sensitive coating that lets a fab transfer circuit patterns onto a silicon wafer, like using a stencil on a microscopic scale. Temporary bonding adhesives hold ultra-thin wafers in place during thinning and stacking, which are required steps in advanced packaging for high-bandwidth memory. (shinetsu.co.jp, evgroup.com) The supply squeeze traces back to naphtha, a petroleum feedstock used to make propylene and then propylene oxide, which sits upstream of PGME and PGMEA. The Elec reported that six of Japan’s 12 naphtha cracking centers had reduced output after Middle East supply disruptions, while Reuters reported Japanese manufacturers were already cutting orders and production in naphtha-linked products by April 15. (thelec.net, usnews.com) The broader disruption began after the effective shutdown of the Strait of Hormuz following the Feb. 28 attacks on Iran by the United States and Israel, according to Chemical & Engineering News. Japan sourced about 40% of its naphtha from the Middle East before the conflict, Reuters reported. (cen.acs.org, usnews.com) The Elec said Japanese naphtha spot prices rose from about $600 a ton before the disruption to $1,190 in early April. Reuters said more than a dozen Japanese companies had already flagged delivery problems or price increases tied to naphtha-based materials. (thelec.net, usnews.com) The immediate risk for memory makers is not just higher costs but process qualification. The Elec reported that if suppliers are forced to change raw materials or formulations, chipmakers could need a product change notice process that can take close to a year before new materials are cleared for mass production. (thelec.net) That timing matters because Samsung and SK hynix sit at the center of the high-bandwidth memory market feeding artificial-intelligence servers. TrendForce reported last year that SK hynix sources most of its photoresists for HBM from Tokyo Ohka Kogyo and relies on other Japanese materials suppliers as well, underscoring how concentrated the chain remains. (trendforce.com) The companies named in current supply discussions include Shin-Etsu Chemical, Tokyo Ohka Kogyo, JSR, Fujifilm and Nissan Chemical, according to The Elec. JSR has been building local production in South Korea, but its Cheongju photoresist plant was reported in 2024 as scheduled to start operations in 2026, which suggests near-term dependence on Japanese supply has not disappeared. (thelec.net, koreaherald.com) Japan’s government has said the country has enough naphtha for about four months and is seeking cargoes outside the Middle East, but Reuters reported downstream firms were still seeing thinner wholesalers halve April supply because May shipments were uncertain. For chip materials, the next question is whether solvent flows resume before fabs have to qualify substitutes they do not want to use. (usnews.com, cen.acs.org)