<div id="readability-page-1">Concentration at extremes: Five tech giants now account for about half of recent S&amp;P 500 gains, with semiconductors at a record 15% of the index’s weight. Winners and laggards: Applied Materials posts record growth, but others like Himax and Power Integrations see sales declines, exposing uneven benefits from AI demand. Bubble risk signals: Analysts draw parallels to the 1990s dot-com era, warning high valuations and narrow market leadership could magnify a downturn.</div>

应用材料

帕沃英蒂格盛

奇景光电

纳斯达克半导体 ETF - First Trust

费城交易所 半导体 ETF - iShares

半导体 ETF - VanEck Vectors

标普半导体 ETF - SPDR

动态半导体 ETF - Invesco

半导体 3 倍做多 - Direxion

<p>五家科技巨头目前占据了近期标准普尔 500 指数涨幅的约一半，半导体在该指数中占据创纪录的 15%。尽管应用材料实现了创纪录的增长，但像奇景光电和帕沃英蒂格盛这样的公司却面临销售下滑，突显出人工智能需求利益的不均衡。分析师警告泡沫风险，指出与 1990 年代互联网泡沫时期的相似之处，认为高估值和市场领导地位的集中可能加剧经济下行</p>

人工智能芯片的上涨推动了市场极端集中风险的加剧