Raman microprobe analysis of patterned Tl-2212 thin films

• Published in: IEEE transactions on applied superconductivity Vol. 7; no. 2; pp. 2126 - 2129
• Main Authors: Myers, K.E., Walls, D.J., Wilker, C., Pang, P.S.W., Carter, C.F.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-06-1997; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Circuit properties; Electric variables; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Laser modes; Laser transitions; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Pattern analysis; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Spectroscopy; Superconducting devices; Superconducting films; Superconducting materials; Superconducting transition temperature; Transistors; Yttrium barium copper oxide
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/77.621012

We have used MicroRaman spectroscopy to evaluate the effects of ion-milling on the exposed edges of patterned Tl/sub 2/Ba/sub 2/CaCu/sub 2/O/sub 8/ (Tl-2212) lines. Raman microprobe has previously been used to evaluate oxygen loss at the edges of patterned YBCO lines. The results indicated that appreciable oxygen loss was caused by ion-milling under certain conditions. oxygen loss at the edges will decrease non-uniformly the effective width of the superconducting line. This can, in turn, impact the electrical characteristics of patterned devices. Using the 633 nm lined of a HeNe laser, we have measured the Raman spectrum scanning across patterned and unpatterned regions of several Tl-2212 films with a mapping stage. It is well known that the Raman peak at /spl ap/497 cm/sup -1/ corresponds to the Cu-O(2) stretching mode and is correlated with the superconducting transition temperature of the material. No appreciable variation in the center frequency of the Cu-O(2) peak was observed indicating thallium cuprate films are not degraded by our patterning process, even at the edges. Variations in the power handling of Tl-2212 co-planar lines, as determined by measurement of the Third Order Intercept, were not correlated with the Raman results.