FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W102543840> ?p ?o ?g. }

• W102543840 abstract "The integrated circuit industry builds integrated circuits (IC’s) by placing many layers of semi conductive material on top of each other, the smallest details in such a layer are called features. Each layer has its own specific layout and will form together with the other layers three dimensional structures such as transistors, diodes or resistors. The final result is an integrated circuit which is called a chip of which a large number of them are fabricated all at once on a round silicon wafer. A position error between these two layers is called an overlay error, the final chip might not function correctly or not at all if this overlay error exceeds certain limits. It is important to minimize this error to obtain a high yield per wafer. As the features are getting smaller in size, the position of a ’new’ layer with respect to the layer below becomes more critical. High end position measurement equipment is required to minimize this overlay error. The lithography-machines involved with the production of these IC’s are expensive due their advanced technology and are therefore subject to high wafer throughput to reduce costs. These processes require thus a measurement tool which can measure with low measurement uncertainty to minimize the overlay error, while allowing for high target velocity. A laser interferometer is such a measurement tool which is able to measure accurate and fast enough to be used for these processes. The laser light required by interferometers to operate in current lithography-machines is guided along corners by mirrors, over meters long optical pathways. This method of light transport is sensitive for environmental disturbances and requires realignment once maintenance is carried out, this is a time consuming and thus costly process. The current interferometer systems also contain small periodic nonlinearities, this nonlinear error presence in the position measurements will become problematic for future systems which require increasingly smaller overlay errors. At the TU Delft a theoretical periodic error free type of interferometer has been build (see Figure 6), based upon spatial separation of optical measurement pathways. This system has shown to operate with sub-nm measurement uncertainty (see Appendices B.1 and B.2) using free-space source frequency delivery. Replacing the free-space beam delivery by fiber-coupled delivery allows for modular plug-and-play systems. No more sensitive to air turbulence, but the light transported by the fibers is unfortunately negatively affected by several phenomena and requires more in depth research. The Delft interferometer concept (Figure 6) knows multiple configurations, two of them have been build for this research: the Delft Corner Cube- and the Generalized Delft-configuration. Three measurement systems have been realized to research operation when the source frequencies are delivered by different types of fibers. The first system, System I, concerns the Generalized Delft configuration with free-space beam delivery with the purpose of reproduction of previous results (see Appendices B.1 and B.2). The obtained results serve as reference for the measurements obtained from the second system, System II. In this system the source frequencies are delivered by polarization maintaining single mode fibers (i.e. pmfibers) instead of mirrors. The second system was build study the sub-nm measurement uncertainty using these pm-fibers for beam delivery, instead of free-space beam delivery. The results obtained from this research are published in the first article of this report, Article I: Fiber-coupled displacement interferometry without periodic nonlinearity. The third measurement system, System III, was build to research the performance of graded index multimode fibers (i.e. mm-fibers) for source frequency delivery for the Delft Corner Cube configuration. These fibers allow for easier alignment and higher optical coupling efficiency compared to pm-fibers. However the ease in handling results in lower optical output quality: the fiber does not maintain polarization state, the initial optical wavefront will be deformed during transport and multiple optical modes will be present in its output. The results obtained with this system are published in the second chapter of this report, Article II: Displacement interferometry with fiber-coupled delivery. Conclusions from the research: Yes, it is possible to measure with sub-nm measurement uncertainty using pm-fiber delivered source frequencies for the Generalized Delft interferometer. We have shown that the periodic nonlinearity was not visible down to the noisefloor (40pm). The same conclusion holds for mm-fiber delivered source frequencies using the Delft Corner Cube interferometer. Both fiber-coupled systems show phase broadening behavior in their measurement results, caused by the birefringent nature of the fibers. This behavior can be seen best in the results using mm-fibers. At first sight this fortunately does not affect the measurement uncertainty. Experimental results confirm that fiber induced phase shifts caused by fiber deformation, are canceled out due the configuration of the Delft interferometer and the differential measurement between the photodetectors. The time varying polarization orientation of the light delivered by mm-fibers in System III, results in interference fluctuations as expected. Nevertheless, the interference signal was not lost during measurements and the fiber coupled system can still measure with sub-nm measurement uncertainty. Building the two fiber coupled systems (System II & III) has shown that pm-fibers require much effort regarding alignment and obtaining a sufficiently high optical coupling efficiency. The finally achieved optical output was of high quality. Multi mode fibers behaved opposite, they were very easy in handling but resulted in a less high optical output quality. Using fiber delivery for the Delft interferometers opens the way towards the design of a modular fibercoupled sub-nm interferometer measurement system. The optical symmetry of the design has shown to be very robust towards phase disturbances, but more research is required regarding system robustness and applicability." @default.
• W102543840 created "2016-06-24" @default.
• W102543840 creator A5059515847 @default.
• W102543840 date "2011-10-27" @default.
• W102543840 modified "2023-09-26" @default.
• W102543840 title "Fiber Coupled Sub-nanometer Heterodyne Displacement Interferometry" @default.
• W102543840 hasPublicationYear "2011" @default.
• W102543840 type Work @default.
• W102543840 sameAs 102543840 @default.
• W102543840 citedByCount "0" @default.
• W102543840 crossrefType "journal-article" @default.
• W102543840 hasAuthorship W102543840A5059515847 @default.
• W102543840 hasConcept C119599485 @default.
• W102543840 hasConcept C120665830 @default.
• W102543840 hasConcept C121332964 @default.
• W102543840 hasConcept C127413603 @default.
• W102543840 hasConcept C134146338 @default.
• W102543840 hasConcept C136085584 @default.
• W102543840 hasConcept C160671074 @default.
• W102543840 hasConcept C165005293 @default.
• W102543840 hasConcept C166689943 @default.
• W102543840 hasConcept C192562407 @default.
• W102543840 hasConcept C199360897 @default.
• W102543840 hasConcept C204223013 @default.
• W102543840 hasConcept C24326235 @default.
• W102543840 hasConcept C41008148 @default.
• W102543840 hasConcept C49040817 @default.
• W102543840 hasConcept C530198007 @default.
• W102543840 hasConcept C76155785 @default.
• W102543840 hasConceptScore W102543840C119599485 @default.
• W102543840 hasConceptScore W102543840C120665830 @default.
• W102543840 hasConceptScore W102543840C121332964 @default.
• W102543840 hasConceptScore W102543840C127413603 @default.
• W102543840 hasConceptScore W102543840C134146338 @default.
• W102543840 hasConceptScore W102543840C136085584 @default.
• W102543840 hasConceptScore W102543840C160671074 @default.
• W102543840 hasConceptScore W102543840C165005293 @default.
• W102543840 hasConceptScore W102543840C166689943 @default.
• W102543840 hasConceptScore W102543840C192562407 @default.
• W102543840 hasConceptScore W102543840C199360897 @default.
• W102543840 hasConceptScore W102543840C204223013 @default.
• W102543840 hasConceptScore W102543840C24326235 @default.
• W102543840 hasConceptScore W102543840C41008148 @default.
• W102543840 hasConceptScore W102543840C49040817 @default.
• W102543840 hasConceptScore W102543840C530198007 @default.
• W102543840 hasConceptScore W102543840C76155785 @default.
• W102543840 hasLocation W1025438401 @default.
• W102543840 hasOpenAccess W102543840 @default.
• W102543840 hasPrimaryLocation W1025438401 @default.
• W102543840 hasRelatedWork W15025197 @default.
• W102543840 hasRelatedWork W176505612 @default.
• W102543840 hasRelatedWork W2015313495 @default.
• W102543840 hasRelatedWork W2182102039 @default.
• W102543840 hasRelatedWork W2333156368 @default.
• W102543840 hasRelatedWork W2601865560 @default.
• W102543840 hasRelatedWork W2740517973 @default.
• W102543840 hasRelatedWork W2889604944 @default.
• W102543840 hasRelatedWork W2896493022 @default.
• W102543840 hasRelatedWork W2963001047 @default.
• W102543840 hasRelatedWork W2985696686 @default.
• W102543840 hasRelatedWork W3027496927 @default.
• W102543840 hasRelatedWork W3136969717 @default.
• W102543840 hasRelatedWork W1979294609 @default.
• W102543840 hasRelatedWork W2601639017 @default.
• W102543840 hasRelatedWork W2613533270 @default.
• W102543840 hasRelatedWork W2627007780 @default.
• W102543840 hasRelatedWork W2740848674 @default.
• W102543840 hasRelatedWork W2763744405 @default.
• W102543840 hasRelatedWork W2872081970 @default.
• W102543840 isParatext "false" @default.
• W102543840 isRetracted "false" @default.
• W102543840 magId "102543840" @default.
• W102543840 workType "article" @default.