(574c) Dielectric Constant Measurement of Pure-Silica-Zeolite Fer Single Crystal by Time Domain Reflectometry (Tdr)

Low dielectric constant (low-k) insulators are essential for the development of future generation computer microprocessors with lowering both crosstalk noises and power consumption. The dielectric insulator of choice since the inception of the semiconductor industry has been dense silica that has a k value of approximately 4. One approach to reduce k value is to incorporate porosity into silica. We have been investigating pure-silica-zeolites (PSZs) as possible low-k materials, which have advantages of uniform micro-porosity, high heat conductivity, superior mechanical strength as well as high hydrophobicity over other low-k materials. Two film deposition processes ? in-situ crystallization and spin-on of zeolite (MFI and MEL) nanoparticle suspension have been developed. In these two films, however, crystal boundaries, crystal size, crystallinity, and the presence of the interparticle mesopores can all affect the film properties. Therefore it is interesting to study single crystals to acquire a fundamental understanding of the relationship between the zeolite framework and the k value without the interference of the aforementioned factors both experimentally and theoretically. In this presentation, we will discuss the synthesis of large PSZ FER single crystals (1.3mm*1.0um*40um) and their k (capacitance) measurements by Time Domain Reflectometry (TDR). The k value from theoretical calculation will also be presented. The TDR measurement procedure consists of sending a fast step signal into the line under test and recording the reflected signal versus time. The size of a capacitance connected to the open end of the path can be determined by comparing it to a reference measurement without the capacitance. Quartz single crystal (1.8mm*3.6mm*41µm, Hoffman Materials Inc.) is used to calibrate the setup to the known k value of 4.58 for at 1 MHz. The k value measured for FER single crystal (with organic templates in the framework) is 2.18. The k value of FER without templates is estimated to be 1.78, which is consistent with the energy-minimized calculation value of 1.75 with using the GULP simulation package.