Dan Taroata

High integration density capacitors directly integrated in a single copper layer of printed circuit boards

Direct integration of capacitors in printed circuit boards with high integration densities and electrical properties comparable to surface mount ceramic capacitors is reported, achieving a device-yield of >;90%. The insulation properties are determined through a self assembled monolayer, whereas the dielectric properties are defined by a ceramic thin-film fabricated from chemically modified highly crystalline BaTiO3 and ZrO2 nanoparticles.

Low-cost copper complexes as p-dopants in solution processable hole transport layers

We demonstrate the usage of the Lewis-acidic copper(II)hexafluoroacetylacetonate (Cu(hfac)2) and copper(II)trifluoroacetylacetonate (Cu(tfac)2) as low-cost p-dopants for conductivity enhancement of solution processable hole transport layers based on small molecules in organic light emitting diodes (OLEDs). The materials were clearly soluble in mixtures of environmentally friendly anisole and xylene and spin-coated under ambient atmosphere. Enhancements of two and four orders of magnitude, reaching 4.0 × 10−11 S/cm with a dopant concentration of only 2 mol% Cu(hfac)2 and 1.5 × 10−9 S/cm with 5 mol% Cu(tfac)2 in 2,2′,7,7′-tetra(N,N-ditolyl)amino-9,9-spiro-bifluorene (spiro-TTB), respectively, were achieved. Red light emitting diodes were fabricated with reduced driving voltages and enhanced current and power efficiencies (8.6 lm/W with Cu(hfac)2 and 5.6 lm/W with Cu(tfac)2) compared to the OLED with undoped spiro-TTB (3.9 lm/W). The OLED with Cu(hfac)2 doped spiro-TTB showed an over 8 times improved LT50 li...