scispace - formally typeset
Search or ask a question
Topic

Photomask

About: Photomask is a research topic. Over the lifetime, 7917 publications have been published within this topic receiving 54524 citations. The topic is also known as: photoreticle & reticle.


Papers
More filters
Journal ArticleDOI
TL;DR: The fabricated microneedle arrays enhance collagen permeation through skin and were shown to enhance permeation of collagen through cadaver rat skin, as compared to passive diffusion of collagen.
Abstract: Purpose To fabricate microneedle arrays directly off a photomask using a simple photolithographical approach and evaluate their potential for delivering collagen.

28 citations

Proceedings ArticleDOI
Yuri Granik1
26 Aug 2003
TL;DR: In this article, a variable bias model is applied to the dry etching in mask fabrication, which can be used to characterize and explain etch behavior in terms of microloading and etch aperture effects.
Abstract: Microloading in photomask fabrication is a key parameter in process optimization. A Variable Bias Model has been successfully used in explaining etch proximity behavior during wafer etching. This model recently became part of the VT5 model suit. In this study, we apply variable bias modeling to the dry etching in mask fabrication. A special etch test pattern is used to characterize etch bias under various process conditions. We show that etch proximity is adequately described by two proximity parameters: density and separation. The model coefficients depend on the process parameters and can be used to characterize and explain etch behavior in terms of microloading and etch aperture effects. Ability to explain mask etching is important for accurate OPC modeling. While some modeling methodologies consider mask and wafer processes as a single "black box," we found that more accurate OPC models are generated by building separate models for mask-making, optical, and wafer processing steps. We show how variable etch model can be used to compensate for iso-dense mask bias and how this step fits into OPC flow.

28 citations

Patent
23 Aug 2001
TL;DR: In this paper, an excimer laser beam source is deployed to project through the photomask on a substrate coated with a polymeric material while the substrate is moving in a direction normal to the straight line direction for the polymeric materials to receive laser beam projection with different time period.
Abstract: A process method of using excimer laser for forming micro spherical and non-spherical polymeric structure array includes a photomask which has a selected curved pattern formed thereon. The curved pattern has non-constant widths along a straight line direction. An excimer laser beam source is deployed to project through the photomask on a substrate coated with a polymeric material while the substrate is moving in a direction normal to the straight line direction for the polymeric material to receive laser beam projection with different time period. The polymeric material thus may be etched to different depth to form a three dimensional pattern desired. By projecting and etching the polymeric material two times at different directions or through different photomask patterns, a sphere like or non-sphere like surface of micro array structure may be obtained.

28 citations

Patent
16 May 1994
TL;DR: In this paper, a photomask for projection exposure is described, comprising opaque stripes respectively arranged on a mask substrate at a given pitch and phase shifters formed alternately on light-transmissive areas between said opaque stripes.
Abstract: A photomask for use in forming a photoresist pattern by projection exposure, comprising opaque stripes respectively arranged on a mask substrate at a given pitch and phase shifters formed alternately on light-transmissive areas between said opaque stripes. The widths of the opaque stripes are larger than those of said light-transmissive areas whereby the edges of said phase shifters on said light-transmissive areas are prevented from being transferred to a wafer.

28 citations

Journal ArticleDOI
TL;DR: In this article, the authors describe soft lithography methods that expand current fabrication capabilities by enabling high-throughput patterning on nonplanar substrates, such as cylindrical surfaces.
Abstract: This paper describes soft lithography methods that expand current fabrication capabilities by enabling high-throughput patterning on nonplanar substrates. These techniques exploit optically dense elastomeric mask elements embedded in a transparent poly(dimethylsiloxane) (PDMS) matrix by vacuum-assisted microfluidic patterning, UV–ozone-mediated irreversible sealing, and chemical etching. These protocols provide highly flexible photomasks exhibiting either positive- or negative-image contrasts, which serve as amplitude masks for large-area photolithographic patterning on a variety of curved (and planar) surfaces. When patterning on cylindrical surfaces, the developed masks do not experience significant pattern distortions. For substrates with 3D curvatures/geometries, however, the PDMS mask must undergo relatively large strains in order to make conformal contact. The new methods described in this report provide planar masks that can be patterned to compliantly compensate for both the displacements and distortions of features that result from stretching the mask to span the 3D geometry. To demonstrate this, a distortion-corrected grid pattern mask was fabricated and used in conjunction with a homemade inflation device to pattern an electrode mesh on a glass hemisphere with predictable registration and distortion compensation. The showcased mask fabrication processes are compatible with a broad range of substrates, illustrating the potential for development of complex lithographic patterns for a variety of applications in the realm of curved electronics (i.e., synthetic retinal implants and curved LED arrays) and wide field-of-view optics.

28 citations


Network Information
Related Topics (5)
Silicon
196K papers, 3M citations
82% related
Chemical vapor deposition
69.7K papers, 1.3M citations
81% related
Nanowire
52K papers, 1.5M citations
80% related
Transistor
138K papers, 1.4M citations
80% related
Thin film
275.5K papers, 4.5M citations
80% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202322
202281
202150
2020124
2019179
2018195