In Search Of Higher Density MIM Capacitor forGaAs RF Applications

Abstract

not Available.

Characterization of ALD Ta2O5, Al2O3, and Ta2O5/Al2O3 Nanolaminate as Metal-Insulator-Metal Capacitor Dielectric for GaAs HBT Technology

“…The reduction of the die size can be achieved by reducing the area of circuit components in the designs. One such component is the metal-insulator-metal (MIM) capacitor, which is a key passive device in GaAs technology (1)(2)(3)(4)(5). The MIM capacitor area in the designs can be reduced by increasing the capacitance density, which can be achieved by using a higher dielectric constant material as the capacitor dielectric.…”

“…It is therefore imperative that the capacitor dielectric material used to fabricate the MIM capacitor has high dielectric constant and capacitance density. Furthermore, the MIM capacitor dielectric in many GaAs circuit designs also has to have high breakdown voltage, as many of these designs that are fabricated using GaAs technologies, including hetero-junction bipolar transistor (HBT) technology, have typically high operating voltage and have transistor output voltage swings that can be 20 V or higher (2,3,6,7). In addition to high breakdown, the MIM capacitor in most GaAs designs and applications also has to have low leakage current, especially when the device operates at high voltage and high temperature.…”

“…In addition to high breakdown, the MIM capacitor in most GaAs designs and applications also has to have low leakage current, especially when the device operates at high voltage and high temperature. Under these conditions, the capacitor leakage current can be significantly higher and the capacitor breakdown voltage can be lower, both of which can lead to early and long term device degradation and reliability failures (3,(7)(8)(9). Furthermore, the capacitance of the MIM capacitor is required to be constant and should not change with applied voltage in many GaAs applications.…”

“…There are several factors that need to be considered when evaluating capacitor dielectric material for GaAs processing technology, including GaAs HBT process. One factor is the processing thermal budget that is limited, due to the degradation of many of the typically used GaAs contact metal materials at temperatures higher than 300 o C (2,3,(10)(11)(12)(13)(14)(15)(16).…”

MIMC Reliability and Electrical Behavior Defined by a Physical Layer Properties of the Dielectric

“…The metal-insulator-metal capacitors has thus become a key building block for mixed signal applications as it offers low parasitic capacitance, especially when fabricated on metal 2 or higher, as well as good linearity since the both electrodes are made of metal. Previous studies demonstrated that because of the higher dielectric constant of the PECVD nitride compare to oxide (5), nitride allows a higher capacitance for the same thickness of the dielectric. This makes it the most popular layer used as MIMC dielectric.…”