Bonding of polydimethylsiloxane microfluidics to silicon-based sensors

Abstract

We investigate bonding polydimethylsiloxane (PDMS) to silicon using a thin (∼2 μm) intermediate adhesive layer stamped onto a PDMS piece prior to bonding. In particular, we compare as adhesive layers Sylgard 184 and 182 curing agents and a UV curable adhesive (NOA 75). We examine the effect of both curing temperature and duration on curing agent bond strength. Bond strengths for the different adhesives are determined by measuring the average burst pressure at a PDMS-silicon interface using a PDMS test design. We find that Sylgard 184 curing agent gives the highest bond strength with burst pressure of 700 kPa or more for curing at either 60 • C for 3 h, 70 • C for 30 min, or 90 • C for 20 min. Curing at room temperature takes substantially more time with an average burst pressure of 433 and 555 kPa for curing times of 16 and 27 h, respectively. In comparison, Sylgard 182 curing agent takes 32 h at room temperature to achieve a burst pressure of 289 kPa, while NOA 75 with a 50 • C 12 h post-UV exposure bake yields a burst pressure of 125 kPa. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

Weak Adsorption-Induced Surface Stress for Streptavidin Binding to Biotin Tethered to Silicon Microcantilever Arrays

“…After functionalization with biotin receptors, we bond our twolayer PDMS microfluidic piece to the silicon die. Since in general receptor molecules can be temperature sensitive (e.g., proteins), we employ our recently developed room temperature bonding technique in which PDMS curing agent is used as the adhesive [25].…”

“…After jetting the receptor molecule solution on select PMCLs the die is incubated for 2 hours at 85% relative humidity (RH) and room temperature and then dried on a hot plate at 37°C. We align and attach the PDMS microfluidics and allow the bonding adhesive to cure for ∼18 hours at room temperature [25].…”

Microcantilever array sensors with integrated PDMS microfluidics

“…Since receptor molecules can be temperature sensitive (e.g., proteins), we developed a room temperature bonding technique in which curing agent is used This work was supported in part by NSF grants ECS-0602261 and IIS-0641973, and DARPA grant 66001-04-8933. 978-1-4244-9289-3/11/$26.00 ©2011 IEEE as an adhesive [7]. Fig.…”

A Rigid Parallel-Plate Artificial Placenta Oxygenator with a Hemocompatible Blood Flow Path

“…Additional gaskets of 3 mm width and 50 mm length were placed in the middle for structural support. The gaskets were all bonded to a single side of a chip (blood gaskets to the front side and sweep gas gaskets to the back side) using PDMS crosslinker 37 . Prior to bonding, all gaskets were measured using a micrometer, and only included if the dimensions were within 1% of the target measurement.…”