Characterization of low‐k benzocyclobutene dielectric thin film

Abstract

This paper reports the characterization of a photosensitive benzocyclobutene (BCB), a low dielectric constant spin‐on polymer for use as interlayer dielectric in the microelectronics industry. Research work is divided into three main sections. First, BCB thin film characterization was done to investigate the effects of curing conditions on BCB film thickness, dielectric properties, optical properties and extent of cure. Thermal stability of BCB was then evaluated using thermogravimetric analysis (TGA) to detect weight loss during thermal curing and degradation. Finally, curing kinetics study was conducted using both differential scanning calorimetry (DSC) dynamic (American Society for Testing and Materials method) and isothermal approaches. The first study shows that determination of vitrification point during thermal curing of BCB is crucial to predict film properties. By curing to just before vitrification, lowest refractive index, hence dielectric constant, could be obtained.

Polymerization of Thin Film Polymers

“…The average total heat of reaction of the fully cured BCB film is about 281.8 ± 5.3 J/g. The results are in good correlation to the measurement of CHAN, who measured a heat of reaction for CYCLOTENE 4024-40 of 291.3 ± 8.8 J/g [17]. The measurement of the heat reaction is strongly dependent on base line settings.…”

Electrically Driven Micro- and Nano-Scale Semiconductor Light Sources

“…The QDs are placed at the center of the intrinsic layer. A key step in the fabrication that makes this structure distinguishable from other planar injection microlasers is the planarization using benzocyclobutene (BCB), a photosensitive polymer frequently used as a low-k dielectric in microelectronics packaging and interconnect applications [18]. This dielectric planarization serves as both a stable physical ground, on which the upper contact can be located, and an efficient electrical isolation layer.…”

Influence of diamond nanoparticles on the thermal properties of benzocyclobutene (BCB)

“…The monomer divinylsiloxane bis‐benzocylobutene (DVS‐bisBCB) material forms a highly crosslinked network when the monomer undergoes a Diel–Alders cycloaddition reaction at temperatures above 225 °C 11. The crosslinked material has the following properties: low dielectric constant (2.65–2.5 (1 MHz–10 GHz)), low moisture absorption (<0.2%), high bonding strength (>50 MPa) and high chemical resistance to extended TMAH etch processes 12–16. It is supplied as a solution of B‐staged BCB monomers (46 wt.%) in mesitylene.…”

“…Bonding with intermediate polymer layers has several advantages over eutectic and direct bonding, particularly low dependence on surface topography, low bonding temperature, no high temperature annealing step, low sensitivity to particles, minimal stress and a low dielectric constant. A commonly used polymer layer for 3D integration with properties that satisfy IC requirements is benzocyclobutene (BCB) 10–14.…”