Photoresist patterning

Alternatively, chemical patterns can be generated by photohthography of a photoresist layer that has been spin-coated over a silane film. Upon irradiation through a mask and subsequent development of the photoresist pattern, the imderlying modified layer is revealed and is able to react with the ONDs. By sequentially irradiating the surface, it is possible to immobihze different ONDs. 

Nguyen, C.V., R.M.D. Stevens, J. Barber, J. Han, and M. Meyyappan. 2002. Carbon nanotube scanning probe for profiling of deep-ultraviolet and 193 nm photoresist patterns. Appl. Phys. Lett. 81 901-903. 

After the patterns on these polymer films are transferred into photoresist films coated on silicon substrates using photolithography, the developed photoresist patterns can serve as a master to make the required PDMS stamps. By combining this method of rapid prototyping with soft lithographic techniques, we can fabricate patterned microstructures of polymers and metals within 24 h of the time that the design is completed. Rapid prototyping makes it possible to produce substantial numbers of simple microstructures rapidly and inexpensively. 

FIGURE 2.14 Electron micrograph of a turn in the channel fabricated in a PDMS chip, created by casting the polymer against a positive relief, which is made of photoresist patterned on a glass substrate. The roughness in the side wall arises from the limited resolution of the transparency used as a photomask in photolithography [1033]. Reprinted with permission from the American Chemical Society. 

Pheochromocytoma (PC12) cells, Schwann (MSC80) cells Plasma induced oxidation of PS guided by photoresist patterns 1998 [97]... 

Fig. 10.33. Registered PDMS/Mylar stamp on Substrate using lock and key mechanism A, B, C and D are optical microscope images of matched relief features of stamp on photoresist patterns of substrate a, b, c, and d are optical microscope images of matched keys of stamp on to locks on substrate.

A photoresist pattern was deposited on a nonlinear diazo dye film and then oxygen etched to form a line of nonlinear and linear sections with a 32 pm QPM period. The upper surface was then planarized with a UV cured resin. A raised QPM +/0 channel waveguide was then formed with three more processing steps [104]. Despite the complexity of the fabrication, losses were below 3 dB cm 1 at 1.59 pm and a maximum SHG figure of merit of 4x10 % W 1 cm 2 was obtained [105,106]. 

Abstract A crucial problem in the manufacturing of high aspect ratio structures in the microchip production is the collapse of photoresist patterns caused by imbalanced capillary forces. A new concept to reduce the pattern collapse bases on the reduction of the capillary forces by adsorption of a cationic surfactant. The application of a cationic surfactant rinse step in the photolithographic process leads to a reduction of the pattern collapse. Physicochemical investigations elucidate the mechanism of surfactant adsorption... 

Preparation of Organic Anti-reflective Coating and Photoresist Pattern... 

Fig.9 Scanning microphotxjgraph of photoresist patterns. (a) without D4-CEL layer, (b) with D4-CEL. Feature definition is enhanced in submicron structure.

Microelectronic device fabrication currently relies primarily upon photoresist processing for integrated circuit pattern delineation. Adhesion of polymeric photoresist patterns, especially those of micron and submicron dimensions, to the required fabrication substrates is of paramount importance. Photoresist image adhesion problems encountered in device fabrication have been solved by chemical interfacial treatments. Current new trends in microelectronic adhesion technology will be described and discussed with emphasis upon the chemical nature of the interface involved as determined by ESCA. 

In microfabrication, photoresist patterning is an important aspect of the definition of microstructures. In this processing, a layer of the photoresist material... 

Figure 15. Low beam energy SEM image of photoresist pattern. (Micrograph taken on a Nanometrics CWIKSCAN III FESEM.J...

Next, the sacrificial layer is deposited as a TEOS (Tetraethylorthosilane) oxide about 1.5 pm thick and is coated with photoresist, patterned and etched to form contact openings to the buried polysilicon layer (Fig. 5.3.11b). 

---