Surface Analysis of DMA-TMS Molecules Adsorbed on SiO₂/Si Substrates for Area Selective Deposition

Area selective deposition is used by the semiconductor industry for bottom-up manufacturing of semiconductor devices.  With this technique, a molecular film adsorbs to regions of the substrate that you would like to block from adsorption of another species.  Dimethylamino-trimethylsilane (DMA-TMS) has a strong affinity for adsorption on SiO₂ surfaces and low affinity for adsorption on most metal surfaces.  Therefore, it can be used to block deposition of metals on SiO₂, while allowing deposition of metals on metals.  Samples of DMA-TMS adsorbed on Si(100) substrates with a 1000 Å thermal oxide and various surface pretreatments have been prepared.  Surface pretreatments include ozone exposure, H₂ plasma treatment, or H₂ plasma pretreatment followed by H₂O vapor exposure after DMA-TMS absorption.  Spectroscopic ellipsometry, FTIR spectroscopy, XPS, and TPD are being used to determine the surface coverage and temperature stability of the DMA-TMS molecules after surface pretreatment.