Resist

About: Resist is a research topic. Over the lifetime, 40991 publications have been published within this topic receiving 371548 citations.

Etching Profiles at Resist Edges: I . Mathematical Models for Diffusion‐Controlled Cases

Abstract: Mathematical models are presented that describe diffusion-controlled etching near resist edges. To understand the role of the various physical parameters, a simple maskless one-dimensional model is studied first. The study of a purely diffusion-contrnlled case suggests that mathematical models for etching problems may be solved by means of perturbation techniques that assume relatively small displacements of the etching surface. The perturbation procedure is then applied to a two-dimensional problem that involves a mask. Assuming a stationary etchant and diffusion control, it is shown that etch rates are largest close to the resist edge. As a result, the etching profile reveals a bulging shape near the mask edge, confirming earlier observations reported in the literature. A case with convection is considered next. It is shown that the very same bulge that resulted from the analysis of the stationary case may also appear when convection plays a role. The perturbation l~rocedure depends upon an important dimensionless parameter ft. Tabulated values of this parameter for various etching systems are presented. Etching of special forms and profiles using resist patterns is often of essential importance in device technology. Two typical examples are shown in Fig. 1. Forms with symmetrical rounded edges or V-shaped grooves are widely used in laser applications. Since the dimensions of such structures are on a micron scale, the accuracy and reproducibility of the etched profiles are critical.

Manufacturing method for a multilayer printed circuit board

Abstract: Disclosed is a method for manufacturing a multilayer circuit board in which landless inter-layer connection is made between a lower-layer electric circuit and an upper-layer electric circuit formed on a substrate. The method of the invention utilizes a single photoresist to form a circuitization layer and the conductive via extending upwardly from it. In the method of the invention a metal layer is applied to the substrate, and photoresist is applied to the metal layer. The photoresist is then exposed and developed to define a resist hole. A via bump is formed in the resist hole. The residual resist is then imaged to form a first circuit pattern in the underlying metal layer. The remaining photoresist is removed from the first metal layer, and an organic dielectric layer is formed on the etched metal layer, the exposed substrate, and via bump. The organic dielectric layer is then flattened or otherwise processed to expose the surface of the via bump. Either a second metal layer or an electronic part is deposited or applied to the exposed top surface of the via bump as an upper-layer electric circuit element.

Lithographical mask for controlling the dimensions of resist patterns

Abstract: A mask for transferring square and rectangular features having critical dimensions (CDs) close to the resolution limit of the exposure tool utilized to perform the transference is described. Intensity modulation lines having the opposite transparency as the rectangular feature to be transferred, and a width significantly less than the resolution of the exposure tool, are disposed within the rectangular feature. The intensity modulation lines have the affect of damping intensity levels on the resist layer in the center of the rectangular feature. As a result, the final CD measurement of the rectangular feature is within the CD tolerance of the original designed CD measurement. In addition, since modulation lines are have dimensions well below the resolution limit of the exposure tool, they are not seen in the final rectangular resist pattern.

Fabrication of plastic microlens arrays using hybrid extrusion rolling embossing with a metallic cylinder mold fabricated using dry film resist.

Abstract: This paper reports a novel and effective method to fabricate microlens arrays on polycarbonate films by hybrid extrusion rolling embossing. The metallic cylinder mold bearing an array of micro-holes is fabricated using photolithography with dry film resist. During the extrusion rolling embossing process, the extruded PC film is immediately pressed against the surface of the roller mold. Under the influence of the rolling pressure and surface tension, an array of convex microlenses is formed. The uniformity and optical properties have been verified. An efficient continuous mass production technique has been demonstrated.