Novel Integration of Metal–Insulator–Metal (MIM) Capacitors Comprising Perovskite-type Dielectric and Cu Bottom Electrode on Low-Temperature Packaging Substrates

Abstract

In this letter, a novel integration scheme, for metal-insulator-metal capacitors comprising perovskite-type dielectrics and Cu-based bottom electrodes, has been demonstrated on low-temperature FR4 packaging substrates. Cu oxidation during dielectric deposition and postannealing is completely avoided by a dielectric-first process flow with Ti as oxygen-getter. By using evaporated barium strontium titanate as capacitor dielectric, a maximum capacitance density (∼1250 nF/cm 2 at 100 kHz) and moderate leakage current (< 4 × 10 −5 A/cm 2 at 2 V) have been achieved with rapid thermal annealing at 700 • C. Higher temperature leads to dielectric degradation. Combined with advanced deposition techniques, this integration scheme enables realization of high-performance embedded capacitors that can be integrated with printed circuit board technology.Index Terms-Annealing, barium strontium titanate (BST), Cu electrode, oxidation, packaging substrate, metal-insulator-metal (MIM) capacitor.

Microwave Synthesis of Noncentrosymmetric BaTiO3 Truncated Nanocubes for Charge Storage Applications

“…We assume that the lower capacitance value for other samples could be due to the polarization. Figure shows the average leakage current density for sample BT15 is 5.78 ± 0.46 × 10 −8 at ±2 V (1 × 10 −8 A/cm 2 at 0 V) , which is lower than previously observed values , . Liao et al have produced a metal−insulator−metal (MIM) capacitor with leakage current of less than 4 × 10 −5 A/cm 2 .…”

“…An MCC stack was fabricated by sputter coating a platinum layer (500 nm) on the upper and lower surfaces of the BT pellet. The ferroelectric properties and leakage current were measured using a Signatone probe station and Teck 609 × 10 −6 high voltage amplifier coupled with a Radiant EF Technology precision LC materials analyzer. Current−voltage measurements were performed using a 610-Keithley electrometer and a variable Aplab DC voltage source.…”

“…Novel synthesis techniques are needed to control the shape and size of the BT nanomaterials to improve the ferroelectrics properties for high charge density capacitor applications. Key property metrics include charge storage capacity , electric field-dependent dielectric constant , leakage current density , and high-frequency losses. Typically, these properties are controlling the microstructure , grain size , and particle size distribution by appropriate sintering parameters and annealing conditions .…”