The more trustworthy Chinese companies are also refusing to do business with Russia so that they don't get sanctioned and lose business with the rest of the world. That leaves Russia with the worst of the worst.
Many ICs are sold in open markets like this: https://n.sinaimg.cn/sinakd10114/107/w1024h683/20220819/c5a8...
Cash and carry, no fux given. You cannot sanction an open market like you cannot sanction open source software.