Substrate crosstalk suppression capability of silicon-on-insulator substrates with buried ground planes (GPSOI)

Experimental s/sub 21/ transmission crosstalk studies have been conducted on silicon-on-insulator substrates with buried ground planes (GPSOI´s) where a 2 /spl Omega/ per square metal-silicide buried ground plane existed between a 15 /spl Omega/-cm p-type silicon substrate and a 1 μm thick buried CVD oxide layer. Locally grounded transmission test structures fabricated on GPSOI were found to exhibit 20 dB increased crosstalk suppression compared to published data for high resistivity (200 /spl Omega/-cm) SOI substrates incorporating capacitive guard rings over a frequency range from 500 MHz to 50 GHz. This represents an order of magnitude improvement in crosstalk power suppression capability compared to existing state-of-the-art suppression techniques in silicon substrates.