Spin-coating process

Figure 3.12. SEM image of a CuIno.7Gao.3Se2 film deposited using a hydrazine-based spin-coating process. The film is deposited on a 500-nm-thick layer of Mo on a glass substrate.

In the example of Fig. 7.15 [43j rhodium particles have been deposited by spin coat impregnation of a Si02/Si substrate with an aqueous solution of rhodium trichloride. After drying, the particles were reduced in hydrogen. The images show samples prepared at three different rotation speeds in the spin coating process, but with concentrations adjusted such that each sample contains about the same amount of rhodium atoms. The particles prepared at high rotation speeds are smaller, which... 

Several detailed analyses of the spin coating process have been conducted (Bornside et al., 1989 Emslie et al., 1958 Meyerhofer, 1978 Yonkoski and Soane, 1992). The analyses conducted by these authors have been shown to hold for a variety of volatile organic solvents (Birnie, 1997 Paul et al., 1996). However, this model may not apply well to spin coating in C02 because coatings from C02 are formed under drastically different conditions. This difficulty in relating the conventional process to C02-based spin coating is illustrative of the hurdles encountered when developing new processes in C02. 

Different approaches to obtain wrinkles in thin polymer sheets were presented by Harrison and Stafford [53, 54], Thin polyethylene (PE) sheets were first spin-coated onto silicon wafers and subsequently transferred to a relatively thick slab of PDMS by releasing the film in water. This technique takes advantage of the tunable film thickness by the spin-coating process (spin velocity, concentration of polymer solution) as well as the water-insoluble nature of PE. Wrinkles were induced by either compressing the PDMS-PE-bilayer setup [54] or depositing the PE-sheet onto a prestrained PDMS slab and releasing the strain afterwards [53],... 

Figure 40. 5K (dotted) and 300 K (solid) magnetic susceptibilities of 0.20% Mn2+ ZnO nanocrystals (o) and several thin films (A-C) prepared by spin-coat processing of the nanocrystals. [Adapted from (54).]... 

All sensitive layers were prepared from solutions of Makrolon in mixtures of chloroform and dichlorobenzene by a spin-coating process. By adjustment of the rotation speed and time the thickness of the layers were varied between 35 nm and 455 nm. Layer thicknesses and refractive indices were determined by spectral ellipsometry. Furthermore the polymer thicknesses were verified by a surface profilometer (Alpha Step 500, Tencor Instruments, Mountain View, USA). 

Processable conjugated polymers can readily be incorporated into electronic devices through the spin-coating process. The devices that have attracted most attention are field effect transistors (FETs) and thin film diodes, the latter primarily as light emitting diodes (LEDs). Typical structures are shown in Fig. 9.28. 

The spin-coating process allows the preparation of uniform thin films on plane snbstrates . In a typical spin-coating experiment the precursor solution is placed onto the center of the substrate, which is then rotated at high speed (typically between 800... 

FIGURE 3. Schematic view of the spin-coating process... 

The Morphology Control of Polymer Thin Films via the Spin-Coating Process... 

Thin zeolite membranes can also be prepared through a spin-coating process of a nanoparticle suspension. Yan and coworkers synthesized silicalite-1 and silicalite-2 in a nanoparticle suspension using a two-stage hydrothermal process.[138,139] First, the precursor... 

Meerholz and coworkers incorporated the HTM (triphenyldiamine derivative) into the backbone of SPF to elevate the device efficiency through promoting hole injection/transport properties [24]. The cross-linkable oxetane-functionalized SPF derivatives 10-12 were also synthesized to realize full color display via spin-coating processes. The resulting EL devices (ITO/PEDOT PSS/10, 11, or 12/Ca/Ag) showed maximum efficiencies of 2.9, 7.0, and 1.0 cd A-1 for blue, green, and red emissions, respectively. 

The process starts with contacting a porous support with the colloidal precursor solution in a dip-coating or a spin-coating process. Film formation starts either with a film-coating or a slip-casting mechanism as will be discussed below. 

In the spin-coating process the liquid is applied to a rotating plate and is distributed across the plate by centrifugal forces [1,8]. 

Y. Huang, K. Chou, Studies on the spin coating process of silica films, Ceram. Int. 29, 485-493 (2003). 

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