CHARACTERIZATION OF A POSITIVE-TONE WET SILYLATION PROCESS WITH THE AZ-5214(TM) PHOTORESIST

A liquid-phase (wet) silylation process has been developed using the c ommercial photoresist AZ 5214(TM), and I-line lithography. The resist is dry developed with O-2, reactive ion etching (RIE); a subsequent CH F3/SF6 RIE, transfers on oxide lines finer than the theoretical resolu tion limit of the lithographic step. Proton nuclear magnetic resonance (NMR) spectroscopy, Rutherford backscattering spectroscopy (RBS), and scanning electron microscopy (SEM) of submicron patterns are used to characterize the process. Their results are consistent with each other , provding Si densities ranging from 20 to 200 x 10(15) atoms/cm2 and Si depths of a few hundred nm. The silylation speed can be as high as 700 nm/min, and is reduced at increasing concentrations of the silylat ing agent, and at the finest patterns. We demonstrate here that NMR is an excellent method of qualitative and quantitative analysis of silyl ated films.