日本半导体：硅片短缺显现……但存在高风险假设

Japan Semis: Silicon wafer shortage in sight... but with a highlyrisky assumption in the nextthree years, driven by increased memory usage and wafer-to-wafer bondingtechnologies.DRAM wafer benefits from HBM consuming 3-4x wafers per bit comparedto DDR5, NAND adopting wafer-to-wafer bonding (CBA) to separately fabricate the logiccapacityandadoption of BacksidePower (BSPDN)uses 2wafers per chip.Ourrawsiliconwafersupply-demandmodelisavailablefordownloadhere +85229185704david.dai@bernsteinsg.com +85221232683jack.lin@bernsteinsg.com +85221232632juho.hwang@bernsteinsg.com In the meanwhile,ex-China silicon wafer supply is only growing at 3% CAGR.Theglobal ex-China silicon wafer supply is concentrated with top 5 taking >90% share. Asthe industry is in oversupply post-COvID, the supply expansion is very limited.The endcustomers inventory is high at ~4 months, twice as much as normal level. Utilization of rawwaferproducers are onlyat~85%.The willingnessto expandcapacityislow,andSUMcOjust canceleda plan to build a new factory in 2029.Even if they decide to restart, ittakes 3years to build anewfactory +442077621857carmine.milano@bernsteinsg.com Silicon wafer shortage in sight? With demand growth, we expect the end customerswafer inventory to drop substantially this year,and normalizes to 2 months by the end of2025to 2027,and it's easyto drawthe conclusion that wafer shortage is coming in 2027,leading to>100% utilization, price hikes,newfavorable LTAs, margin expansion...whichexplains the strong interest to long wafer suppliers now.We can see12% oversupply in2025turning into 7% shortage in 2028,assuming... ... China doesn't spoil the party?The above analysis ignores China wafer suppliersthat Chinese suppliers will not be ableto address the global market as the quality is lower,leading to lower customer yield.But they are perfectly able to meet the demand of NANDand mature logic which are ~60% of wafer demand and are not demanding in wafer quality.Assuming China increases export of silicon wafers, the global suppliers'UTR will remain<95%inthenext3years. SUMcotrademay beOK...but onlyas a trade.SUMCO price surged 45%YTD dueto the cycle turn argument, and global peers (Shin-Etsu, GlobalWafers, Siltronic, all notcovered)showed same trend.Now trading at 1.32xP/B, there is probably stll some upsidetogofor SUMco (bullsexpect1.5-2x),especiallywhen theupcoming earning showsinventory starting to drop significantly. But fundamentally, the threat from Chinese suppliersis real, and investors shouldn't overstay the welcome.We rate SUMCO Market-Perform,PT=￥1,530.00 Global ex-China silicon wafer supply onlygrows at 3% CAGR,whileChina expandsmuchfasterIf Chinese suppliers stay in China, it's easy to see wafer shortage in ex-China... but that's a big IF..Willthe Chinese suppliers be able to address the oversea market?.8Stock implications: probably good as a trade for now... but it's just a trade internationalincumbents;GlobalSemis:RiseoftheChinesewafersuppliers;SUMCO:Overhypedexpectationsresetaftersharecorrection; upgrading to Market-Perform).In this report, we update our latestviews of the silicon wafer supply anddemand inthe next three years. Key takeaways: Bonded to Array (CBA) and Backside Power Delivery Network (BSPDN). :Meanwhile,ex-China silicon wafer supply is expected to grow atonly 3% CAGR,with current utilization remaininglow at~85% due to elevated end-customer inventory of ~4 months.It is easy to concludethat inventory could normalize this year and wafer oversupply could turn into shortage in2027,drivingutilization to>100%,alongside price hikes,more favorable long-termagreements (LTAs),and margin expansion.But don'tforget China which is increasing capacity by77% overthe next three years.Once China rampsup silicon waferexports, global suppliers'utilization is likely to remain<95% over the next three years. Details below,and ourrawsilicon wafersupply-demandmodelisavailablefordownload here Weforecastglobal silicon waferdemandto growat 12%2025-2028CAGR(Exhibit 1),drivenby: DRAM:Global DRAM wafer capacity increase is the biggest growthdriver,especiallyHBM whichconsumes 3-4x wafersper bit compared to DDR5 (Exhibit 2).NAND:While NAND wafer shipments are not growing significantly,NAND is rapidly adopting wafer-to-wafer bondingexplained this technology in Global Semis: NAND hybrid bonding-the next frontier of advanced packaging.As such,NAND wafer usage is growing at a 14% CAGR, well above wafer output growth (Exhibit 3).Logic: While mature logic is seeing limited growth,advanced logic wafer usage is growing rapidly on Al demand,andBackside Power (BSPDN) requires 2 wafers per chip (Exhibit 4). This was explained in Global Semis: Backside PowerAdvanced packagingto extend Moore's Law.Looking at Chinaand ex-China separately,China wafer demand growth is much higherat+18.2%,whileex-China demandgrowth remains healthy at +11% (Exhibit 5 and Exhibit 6).This is mostly driven by China's effort to localize semiconductorproduction,