Surface plasmon waveguide devices with Tg-bonded Cytop claddings

Abstract

Articles you may be interested inModeling of long range surface plasmon polariton cladded membrane waveguides with integrated grating couplers as hydrogen sensors A versatile liquid-core/liquid-twin-cladding waveguide micro flow cell fabricated by rapid prototyping Appl. Phys. Lett. 95, 163702 (2009); 10.1063/1.3249771 Long-range surface plasmon-polariton waveguides and devices in lithium niobateSurface plasmon waveguide devices were fabricated in symmetric Cytop claddings by bonding the claddings with Au waveguides and microfluidic channels at the interface. Au features were patterned and deposited on the bottom wafer and microfluidic channels were patterned and etched into the top wafer. Aligned wafer bonding and annealing were performed at temperatures slightly above the glass transition temperature (T g ) of Cytop. The bond strength is high, allowing dicing, ultrasonic cleaning, and polishing of facets. The bond is also of good hermiticity as assessed by fluid injection, and of reasonable optical quality as verified by measurements of long-range surface plasmon propagation at k ¼ 1310 and 1550 nm.

Wafer-bonded surface plasmon waveguide sensors with in-plane microfluidic interfaces

“…Such biosensors have been used for many applications, including, e.g., biomolecular interaction analysis [12], blood typing [13], the detection of Dengue infection in patient plasma [14,15], the detection of leukemia in patient serum [16], and the detection of bacteria in urine [17]. LRSPP waveguide biosensors offer the further advantages of compactness, integration and low cost, given that wafer-scale fabrication techniques can be applied [18]. In addition to attenuation-based sensing [11][12][13][14][15][16][17], phase-based sensing is also possible using integrated interferometric structures [19,20].…”

Fabrication of Long Range Surface Plasmon Polariton Biosensors incorporating Optical Waveguides and Encapsulated Microfluidic Channels via Wafer Bonding"

“…As reported in [64] [49] the cracking was a major problem in the fabrication of upper CYTOP cladding. In addition, waveguide deformation is also reported, and both problems arise from the same cause; the inability of CYTOP to chemically cure as reported in [65].…”

“…In addition, the waveguides were slightly deformed along the edges at the bonding interface at a few locations. In such a case, one of the possible solutions is burying waveguides in CYTOP by etching shallow trenches as discussed in [65] which is implemented in this work with modifications.…”

“…The trenches were etched in the MARCH RIE system. The trench etching process is adapted from [65] [72] with modifications. To etch a trench as shallow as 35 nm in the lower CYTOP clad using an RIE etch, a precise and repeatable process is essential.…”

“…For example, baking bilayer stack above Tg of CYTOP causes the gold waveguides to deform, and high ramp rate may cause the thin SiO2 film to fail[49]. The solutions to the issues have been proposed and implemented in[65] by fabricating the upper CYTOP cladding and microfluidic channels on separate substrates.…”