SBIR Phase I: Ferroelectric Thin Films on Low-Cost Substrates for Wireless Applications

Ngimat Co., Lexington KY

Investigators

Abstract

This Small Business Innovation Research (SBIR) Phase I project is aimed at producing high-quality BaxSr1-xTiO3 (BST) films with low dielectric losses and high tunability on low-cost substrates (sapphire and metal). These ferroelectric thin films are of great interest for advanced tunable microwave devices that are being used in, for example, wireless telecommunication hardware. To date, there are only two process technologies (PLD and MOCVD) that allow depositing BST onto sapphire and none exists for depositing BST onto metallic substrates. Hence, there is a compelling technical and commercial need to develop an advanced deposition process that can overcome these apparent shortcomings. In related work we have shown that the proprietary Combustion Chemical Vapor Deposition (CCVD) process can deposit high-quality, epitaxial BST thin films onto a variety of substrates. The goal of this Phase I program is to demonstrate the capability of the CCVD process to produce tunable microwave devices using CCVD-grown thin films of ferroelectric BaxSr1-xTiO3 (BST). The effect of systematically varying film composition and substrate on thin-film properties will be investigated with a special focus towards the intended wireless applications. The market for low cost, tunable microwave devices continues to grow every year as the world untethers itself from the telephone lines. Over $300 million worth wireless handsets were sold this past year and that number is projected to rise to over $1.5 billion by the year 2005. Tunable devices also benefit the manufacturers of RF radios, satellite communication equipment, and active antennas. There is a tremendous interest in low-cost phase shifters with a price target of approx. $5. This goal is achievable with the right combination of advanced thin films, low-cost substrate and high-volume deposition technology.