Coplanar ferroelectric phase shifter on silicon substrate with TiO/sub 2/ buffer layer

In this paper, a BST coplanar phase shifter with differential phase shift of 98/spl deg/ at 50 V and FoM of 46.7/spl deg//dB has been realized. The potential feasibility of integrating BST films into Si substrate as microwave phase shifter and/or coplanar waveguide tunable devices with TiO/sub 2/ thin film buffer layer has been successfully demonstrated. TiO/sub 2/ as buffer layer has been successfully grown onto Si substrate by ALD (atomic layer deposition).