Improving images from a near-field scanning microwave microscope using a hybrid probe

We fabricated a near-field scanning microwave microscope (NSMM) using a hybrid tip combining a reduced length of the tapered part with a small apex. In order to understand the function of the probe, we fabricated three different tips using a conventional chemical etching technique and observed three different NSMM images for patterned Cr films on glass substrates. These probe tips were coupled to a high-quality dielectric resonator at an operating frequency f=4.46 GHz. By using the hybrid tip, we demonstrated an improved, high-contrast NSMM image of lambda phage DNA on a glass substrate. (C) 2003 American Institute of Physics.