Hi, all: Thanks for many information about ZnO sputtering which I posed last time. And I have another question about selective etching. Does anyone know how to etch Ti but not ZnO? I know some literature etch Al but not ZnO, but it's hard to find information etch Ti but not ZnO. In my own experiment, I try Ti etchant(HF , RCA1, NaOH), but they also etch ZnO. Is that Zn active than Ti? Thanks any replay. Jacob Yeh --------------------------------- Yahoo!©_¼¯¹q¤l«H½c 250MB ¶W¤j§K¶O«H½c¡A«H¥ó¦ A¦h¤]¤£©È¡I°¨¤W¨Ï 65;Î