AloStar Bank of Commerce is paying 1.05% APY on 6 month CDs. This is the best nationally available deal on CDs for this term.
The next top rate is from Aurora Bank, which is offering 1.04% APY. The certificates of deposit can be availed on a deposit of at least $1,000. At Ascencia, you can earn 1.02% APY on 6 month CDs, with a minimum deposit of $500.