Trilayer process

Figure 2.16, Scanning electron micrograph of resist images generated in a trilayer process. This figure shows the vertical walls and the absence of line width variations where the pattern crosses topographic features. Reproduced from reference 3. Copyright 1984 American Chemical Society)...

A simplification of the trilayer process involves combining the oxygen etch resistance of the silicon dioxide layer and the imaging characteristics of the top imaging layer (Figure 13). This converts the trilayer scheme to a bilayer scheme and eliminates one coating step and one etch step. In this process... 

The typical properties of some commercial microporous membranes are summarized in Table 4. Celgard 2730 and Celgard 2400 are single layer PE and PP separators, respectively, while Celgard 2320 and 2325 are trilayer separators of 20 and 25 fim thickness. Asahi and Tonen separators are single layer PE separators made by the wet process. Basic properties, such as thickness, gurley, porosity, melt temperature, and ionic resistivity are reported in Table 4. These properties are defined in section 6.1.3. 

Fig. 1. Special equipment required to fabricate low-temperature superconducting junctions. Josephson junctions are comprised of aluminum oxide sandwiched between layers of niobium. These trilayer devices are considered vital to the very-high-speed signal processing demands of next-generation computers, radar, and communication systems. Shown in illustration is scientist Dr. Joonhee Kang. (Westinghouse Electric Corporation)...

Figure 2. M-H loops of the FM/AF/FM trilayers at 300 K for various AF thicknesses showing the three types of reversals. For tmo 10 nm both FM layers reverse in a single process. The formation of an intermediate plateau between two distinct reversal fields starts at tNi0 20 nm. For h o > 40 rnn, the plateau remains independent of tNi0.

In [55] a large-area fabrication of hexagonally ordered metal dot arrays with an area density of 10u/cm2 was demonstrated. The metal dots were produced by an electron beam evaporation followed by a lift-off process. The dots size was 20 nm dots with a 40 nm period by combining block copolymer nanolithography and a trilayer resist technique. A self-assembled spherical-phase block copolymer top layer spontaneously generated the pattern, acting as a template. The pattern was first transferred to a silicon nitride middle layer by reactive ion etch, producing holes. The nitride layer was then used as a mask to further etch into a polyamide bottom layer. 

This chapter describes the physical processes that occur in free-standing ultrathin trilayer films consisting of a fluid layer sandwiched in between two solid layers. We have recently referred to these films as Dutcher films these are named... 

The trilayer PPy actuator is illustrated in Fig. 5.1. On both sides of the actuator are PPy layers. In the middle is an amorphous, porous pol3cvinyli-dene fluoride (PVDF) layer that serves both as a backing material and a reservoir for the electrolyte, which allows the actuator to work in air for a limited period of time (up to several hours). During the electrochemical deposition of the PPy layers, anions A in the electrolyte are introduced into the polymer matrix, which is a process called doping. When a voltage is ap-... 

Trilayer PPy actuators were first reported by the Intelligent Polymer Research Institute at the University of Wollongong, Australia. A description of the fabrication process can be found in, e.g., [Wu et al. (2006)], and it is provided here for completeness. The PPy layers are electrochemically deposited on both sides of a gold-coated porous PVDF film. The PVDF film obtained from Sigma-Aldrich Co., has a thickness of 110 lam with pore size of 0.45 /Ltm. Gold layers of 100 nm are sputtered on both sides of the PVDF,... 

Trilayer PPy petals were cut from a sample fabricated using the procedure described in Section 5.2. The body of the micropump, including its flap check valves, was fabricated with polydimethylsiloxane (PDMS) using MEMS processes [Fang and Tan (2010)]. Fig. 9.23 shows the assembled... 

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