AI Borrowing Boom Raises Japan’s Corporate Funding Costs

The global race to build artificial-intelligence capacity is spreading from chips and electricity into debt markets. Amazon, Microsoft, Alphabet and SoftBank are among the technology groups raising capital to fund hundreds of billions of dollars in data centers, advanced servers and power infrastructure. Heavy corporate issuance can crowd out other borrowers and lift benchmark yields, posing an especially sharp adjustment for Japanese companies accustomed to decades of near-zero rates as they finance semiconductor revival and sovereign-AI projects.

As of Sept. 3, 2026, Japan’s 10-year government bond yield had climbed to about 2.95%, its highest level in nearly three decades, while US federal debt was approaching $40 trillion. Rising sovereign issuance and persistent inflation concerns are pushing up corporate borrowing costs as well. That raises the hurdle rate for multitrillion-yen initiatives including Rapidus’s planned 2-nanometer production, Taiwan Semiconductor Manufacturing Co.’s Kumamoto expansion, and sovereign-AI data centers backed by SoftBank and Japanese telecom operators, forcing sponsors to demonstrate faster and clearer returns.