Eligible collateral under the Bank Term Funding program must be "direct obligations of, and obligations fully guaranteed as to principal and interest by, the United States", this covers assets such as U.S. Treasuries, U.S. agency securities, and U.S. agency mortgage-backed securities, but importantly doesn't cover any of SVB's $72bn loan book. (It does cover much of their $90bn of remaining securities that weren't transferred.)

First Citizens does however have existing assets that would count as eligible collateral.