Tunable dielectric performance of porphyrin based metal−organic frameworks with polar molecule confinement

Abstract

With the rapid development of 5G communications, the designs of metal-organic frameworks (MOFs) with high porosity, tunable structural features as well as low dielectric constant have been gradually focused and developed with potential to be used as an interlayer dielectric (ILD) material in integrated circuits (IC). In this work, porphyrin based metal-organic frameworks (AlOH)2H2TCPP, denoted as Al-TCPP-MOFs, were synthesized by hydrothermal reaction. The structural, thermal and dielectric properties of Al-TCPP-MOFs, Al-TCPP-MOFs-H2O (polar water molecular confinement on Al-TCPP-MOFs), and Al-TCPP-MOFs-DMF (polar DMF molecular confinement on Al-TCPP-MOFs) were characterized systematically. The results showed that the Al-TCPP-MOFs material exhibited high porosity, as well as uniform lamellar structure. The role of polar molecular confinement effect of different coordination systems on the dielectric performances of MOFs were investigated, and the relative dielectric constant of Al-TCPP-MOFs was found to be as low as 2.3 at 103 Hz. Moreover, the Al-TCPP-MOFs exhibited excellent stability of dielectric properties under a wide temperature range and reliable thermal stability up to 420 °C. The preparation of low dielectric constant porphyrin-based metal–organic framework with a high thermal stability opens up a new direction for the application of MOFs in electronic devices of 5G era.