Increased Multilayer Fabrication and RF Characterization of a High-Density Stacked MIM Capacitor Based on Selective Etching

Journal Article · Tue Jul 01 00:00:00 EDT 2014 · IEEE Transactions on Electron Devices

DOI:https://doi.org/10.1109/TED.2014.2325491· OSTI ID:1211417

Tseng, VFG; Xie, HK

This paper presents the fabrication and characterization of a high-density multilayer stacked metal-insulator-metal (MIM) capacitor based on a novel process of depositing the MIM multilayer on pillars followed by polishing and selective etching steps to form a stacked capacitor with merely three photolithography steps. In this paper, the pillars were made of glass to prevent substrate loss, whereas an oxide-nitride-oxide dielectric was employed for lower leakage, better voltage/frequency linearity, and better stress compensation. MIM capacitors with six dielectric layers were successfully fabricated, yielding capacitance density of 3.8 fF/mu m(2), maximum capacitance of 2.47 nF, and linear and quadratic voltage coefficients of capacitance below 21.2 ppm/V and 2.31 ppm/V-2. The impedance was measured from 40 Hz to 3 GHz, and characterized by an analytically derived equivalent circuit model to verify the radio frequency applicability. The multilayer stacking-induced plate resistance mismatch and its effect on the equivalent series resistance (ESR) and effective capacitance was also investigated, which can be counteracted by a corrected metal thickness design. A low ESR of 800 m Omega was achieved, whereas the self-resonance frequency was >760 MHz, successfully demonstrating the feasibility of this method to scale up capacitance densities for high-quality-factor, high-frequency, and large-value MIM capacitors.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• DOE Contract Number: DE-AR0000105
• OSTI ID: 1211417
• Journal Information: IEEE Transactions on Electron Devices, Vol. 61, Issue 7; ISSN 0018-9383
• Country of Publication: United States
• Language: English