Multiphoton lithography

[2] As a result, a given sample relative to the focused laser beam can be scanned while changing the resist's solubility only in a confined volume.Concretely, those regions of the laser beam which exceed a given exposure threshold of the photosensitive medium define the basic building block, the so-called voxel.Other parameters which influence the actual shape of the voxel are the laser mode and the refractive-index mismatch between the resist and the immersion system leading to spherical aberration.It was found that polarization effects in laser 3D nanolithography can be employed to fine-tune the feature sizes (and corresponding aspect ratio) in the structuring of photoresists.This proves polarization to be a variable parameter next to laser power (intensity), scanning speed (exposure duration), accumulated dose, etc.Inorganic glass and ceramics have better thermal and chemical stabilities than photopolymers do, and they also offer improved durability due to their high resistance to corrosion, degradation, and wear.[12] Nowadays there are several application fields for microstructured devices, made by multiphoton polymerization, such as: regenerative medicine, biomedical engineering, micromechanic, microfluidic, atomic force microscopy, optics and telecommunication science.They vary in key parameters as geometry, porosity and dimension to control and condition, in a mechanical and chemical fashion, fundamental cues in in vitro cell cultures: migration, adhesion, proliferation and differentiation.[7] To date, atomic force microscopy microtips are realized with standard photolithographic techniques on hard materials, such as gold, silicon, and its derivatives.Nonetheless, the mechanical properties of such materials require time-consuming and expensive production processes to create or bend the tips.
Model of a castle (0.2 mm x 0.3 mm x 0.4 mm) 3D-printed on a pencil tip via multiphoton lithography
Animation of the multiphoton-polymerization process
Schematic representation of the multiphoton writing [ clarification needed ] process.
3D-printedpencilphotolithographyphotoresistsphotomaskstwo-photon absorptionphotosensitiveexcimer laserspolymerizationrapid prototypingthird-order optical susceptibilitysecond-order process with respect to light intensitypolarization effectsmonomerphotoinitiatorinhibitorsacrylatesradical reactionepoxiesspin coatingbakingmicrofluidiccationic polymerizationaspect ratioregenerative medicinebiomedical engineeringmicromechanicatomic force microscopyopticsLab-on-a-chipshear stressesoptical waveguidesresonatorsphotonic crystalsBibcodeJonty HurwitzLasersList of laser articlesList of laser typesList of laser applicationsLaser acronymsChemical laserDye laserBubbleLiquid-crystalGas laserCarbon dioxideExcimerHelium–neonNitrogenFree-electron laserLaser diodeSolid-state laserTi-sapphireX-ray laserLaser physicsActive laser mediumAmplified spontaneous emissionContinuous waveLaser ablationLaser linewidthLasing thresholdPopulation inversionUltrashort pulseBeam expanderBeam homogenizerChirped pulse amplificationGain-switchingGaussian beamInjection seederLaser beam profilerM squaredMode lockingMultiple-prism grating laser oscillatorOptical amplifierOptical cavityOptical isolatorOutput couplerQ-switching