周末复盘稿：三星、SK海力士上周暴跌18%-24%并向韩国半导体材料/设备/零部件供应商扩散，主因为长鑫4F² DRAM进展引发的情绪与外资抛售

The sharp slide in shares of Samsung Electronics (005930.KS) and SK hynix (000660.KS) is spreading to South Korea's chip materials, parts and equipment suppliers. Through early this month, supplier stocks kept climbing even as the large-cap chipmakers stalled, but selling broadened across the sector over the past week. Analysts say worries about Chinese memory makers closing the technology gap and about the durability of artificial intelligence investment have left overall market sentiment and fund flows, rather than individual earnings or growth prospects, driving share prices.
Samsung Electronics fell 17.75% and SK hynix 24.33% between the 12th and 16th of this month, according to the Korea Exchange. The weekly declines were the steepest for both stocks since the fourth week of October 2008, during the global financial crisis, when they dropped 19.3%. Over the same period, Eugene Technology (084370.KS) plunged 25.35%, while LB Semicon fell 22.09%, Hanmi Semiconductor (042700.KS) 21.35%, Hana Micron (067310.KS) 20.21% and Nepes Ark 20.18%.
That marked a clear reversal from the first week of the month. Between the 1st and 8th, Samsung Electronics lost 2.42% and SK hynix 5.35%, yet supplier stocks advanced. KCTech surged 41.07%, Doosan Tesna gained 28.25%, QRT rose 23.96% and Hanyang Digitech added 21.91%. Hanmi Semiconductor rose 4.09%, Nepes 13.46% and Hana Micron 8.13%.
At the time, an improving memory chip market and expectations of expanded capital spending worked in the suppliers' favor. Even if competition among memory makers intensified, investors reasoned, added production capacity and equipment orders would create new business for suppliers. But that divergence collapsed as both the large-cap chipmakers and their suppliers fell together between the 12th and 16th.
The main drag on sentiment across the chip sector has been the technological progress of China's ChangXin Memory Technologies. Reports said the company had advanced its development of 4F² architecture, a next-generation DRAM technology, and plans to unveil server DRAM products using it by the end of the year. The 4F² structure raises DRAM storage density and is also under development at Samsung Electronics and SK hynix. Concerns that Chinese manufacturers may be advancing faster than expected appear to have triggered broad selling in Korean chip shares.
High interest rates and foreign selling added to the pressure. The U.S. consumer price index for September came in above market expectations, fueling concerns about further rate increases, while doubts grew over funding costs and investment returns at AI infrastructure companies. Foreign investors sold a net 11.239 trillion won ($7.9 billion) of shares on the main board between the 12th and 16th, Korea Exchange data showed, about 74% more than the net 6.446 trillion won they sold between the 1st and 8th. Retail investors bought a net 4.312 trillion won and institutions a net 3.418 trillion won over the same period, but that was not enough to absorb the foreign selling.
"When chipmakers increase investment, it can create opportunities for suppliers even if chip prices fall at Samsung Electronics and SK hynix, and that is why their share prices had been diverging," said Kim Hak-kyun, head of the research center at Shinyoung Securities (001720.KS). "Over the past week, suppliers were not adjusting because of their own earnings. Sentiment toward risk assets as a whole deteriorated, and the entire chip sector fell together."