Formulation and Characterization of Sinterless Barium Strontium Titanate (BST) Dielectric Nanoparticle Ink for Printed RF and Microwave Applications

• Published in: Journal of electronic materials 2021-06, Vol.50 (6), p.3241-3248
• Main Authors: Ranasingha, Oshadha K., Haghzadeh, Mahdi, Sobkowicz, Margaret J., Kingsley, Edward, Armiento, Craig, Akyurtlu, Alkim
• Format: Article
• Language: English
• Subjects: Barium strontium titanates; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dielectric properties; Electronics and Microelectronics; Instrumentation; Low temperature; Materials Science; Nanoparticles; Optical and Electronic Materials; Original Research Article; Permittivity; Radio frequency; Solid State Physics; Strontium; Substrates; Temperature dependence
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-021-08915-7

Here, we report a previously unreported low-temperature curable barium strontium titanate (Ba X Sr 1−X TiO 3 ) or BST dielectric nanoparticle ink which shows a high dielectric tunability for printed electronics/additive manufacturing applications. The newly formulated BST ink is optimized to print in aerosol jet printers and can be cured at 150°C, which will allow the fabrication of tunable radio-frequency (RF) and microwave (MW) devices on a wide range of flexible substrates. Characterization of high-frequency dielectric properties showed a high dielectric tunability (~ 15% at 10 GHz with 10 V/µm) and a high dielectric constant (~ 16 at 10 GHz). The linear-reversible tunability, which is very important for tunable devices, was confirmed by the tunability testing at 10 GHz. Characterization of temperature-dependent dielectric properties found < 10% variations of the dielectric constant at 10 GHz from −50°C to 125°C for this BST ink. Detailed information on BST nanoparticle characterization, ink formulation and characterization of dielectric properties is discussed.