The development of optical lithography has promoted the ultralarge scale integration (ULSI) devices. However, is now facing serious obstacles due to limitations in wavelength. Higher resolution with sufficient depth focus most important requirement for ULSI engineers. To satisfy this requirement, many technologies improvement and new image formation such as phase shifting latitude enhancement exposure (FLEX) are reviewed, a future perspective on also discussed paper.

Ultrasmall edge roughness in delineated patterns (nano roughness) is investigated nanostructures made of negative-type electron beam polymer resists by atomic force microscope measurements. Very narrow isolated lines 10–20 nm wide are fabricated with a finely focused provided scanning microscope. A chemical amplification novolak resin-based resist shows nano which cannot be neglected nanofabrication. To investigate the origin roughness, conventional two-component systems microscopically...

The origin of ultra small edge roughness in delineated resist patterns (nano roughness) is investigated from the viewpoint molecular structures base polymers resists. In this article, conventional two-component negative-type electron beam resists are studied to clarify correlation nano with polymers. cresol novolak and polyvinylphenol mixed same concentrations photoactive azide compound. weight-average weight ( M w ) polydispersity / n resins controlled. Nanometer feature microscopic surface...

Spatial filtering at the lens pupil can achieve amplitude superposition for multiple images along light axis and phase control between them. This enhances depth of focus while maintaining high resolution capability in optical lithography. Compared to conventional methods, three times larger is expected hole patterns with 20% improved limit. For general pattern features, a 1.5–1.7 Rayleigh’s

Electron-beam cell projection lithography realizes a high throughput capability suitable for ultra-large-scale integration (ULSI) manufacturing. This method makes it possible to drastically reduce the number of electron-beam exposure shots by utilizing specially shaped beam. beam is created an Si aperture which forms various shapes, coinciding with array each unit ULSI pattern. The also rectangular shape conventional variable-shaped in order create random patterns. An made single crystal...

We have been developing CO₂-Sn-LPP EUV light source which is the most promising solution as 13.5nm high power for HVM EUVL. Unique and original technologies such as: combination of pulsed CO₂ laser Sn droplets, dual wavelength pulses shooting, mitigation with magnetic field, developed in Gigaphoton Inc. The theoretical experimental data clearly showed advantage our proposed strategy. Based on these we are first practical - "GL200E". This means 250W will be able to...

Acid-diffusion effect on nanometer pattern fabrication in a chemical amplification resist, SAL601 (Shipley Co.), is investigated with finely focused electron beam. During postexposure bake (PEB), acid generated by the beam exposure diffuses and assumed to cause size changes. A scanning microscope, S-900 (Hitachi), which has diameter of approximately 2 nm at 5 kV, used make latent images isolated lines resist film. After exposure, films thickness 20 are baked different conditions before...

Since 2002, we have been developing a CO₂-Sn-LPP EUV light source, the most promising solution as 13.5 nm high power (>200 W) source for HVM lithography. Because of its efficiency, scalability and spatial freedom around plasma, believe that scheme is feasible candidate EUVL. By now, our group has proposed several unique original technologies such CO₂ laser driven Sn plasma generation, double pulse shooting higher ionization rate CE, debris mitigation with magnetic...

We have calculated the linear absorption coefficients of various resist polymers using mass at 13 nm and density obtained from graph-theoretical treatment derived by Bicerano. The values indicate that transmittance conventional resists used in 193-nm, 248-nm 365-nm lithography is about 30% when thickness 3000 Å 60–70% it 1000 Å. This shows are suitable for an EUVL (extreme ultraviolet lithography) thin-layer (TLR) process a hard-mask layer, but their large photoabsorption makes them...

This article proposes a new method for proximity effect correction that utilizes newly developed hardware. The algorithm modifies the exposure dose each point by referring to pattern area density map. only additional process in this is virtual make carried out once at first use of large-scale integration circuit and can be processed 30 s. map makes it possible correct from lower-level patterns calculated two maps lower level exposing level. usefulness verified experiments using model patterns.

The Power Spectral Density (PSD) function for a large-field EUV exposure system is used to compute the impact of flare on critical dimension (CD) control masks exhibiting Cr density changes that result in cross-field variation. It shown open field must be controlled 11 percent 30 nm isolated features and 6 20 an NA equals 0.25 assuming +/- 3 CD budget allocated flare. Based these results individual mirror surface roughness specifications mid-spatial frequencies about 0.14 0.11 RMS,...

Molecular weight distribution effects of novolak resin-based chemical amplification negative resist systems are investigated for electron-beam lithography. The consist onium salts as an acid generator, a methoxymethyl melamine crosslinker, and conventional/fractionated resin matrix. Delineated patterns both types compared to evaluate submicron-scale resolution. conventional system shows higher contrast than the fractionated one. High aspect ratio resolved novolak-based resist, whereas poor...

Since 2002, we have been developing a CO₂-Sn-LPP EUV light source, the most promising solution as 13.5 nm high power (>200 W) source for HVM lithography. Because of its efficiency, scalability and spatial freedom around plasma. Our group has proposed several unique original technologies; 1) CO₂ laser driven Sn plasma generation, 2) Double pulse shooting higher ionization rate CE. 3) debris mitigation with magnetic field, 4) Hybrid system that is scalable combination...

We evaluated the accuracy of point diffraction interferometer, which has been completed at Atsugi Research Center’s Association Super-Advanced Electronics Technologies for precise measurement extreme ultraviolet lithography optics. To evaluate absolute accuracy, more precision is required. A pinhole with 0.5 μm diameter was used to generate a near completely spherical reference wave front, and helium gas filled inside chamber suppress air turbulence. With this apparatus, 0.04 nm...

Practical resolution, the minimum feature size with a depth of focus (DOF) required for LSI fabrication process, is analyzed. Dependence practical resolution on various factors, such as optical system parameters (exposure wavelength lambda , and numerical aperture NA), resist processes, DOF, investigated. It shown that in sub-halfmicrometer region not improved, may even be degraded, increasing NA. Furthermore, improvement by NA becomes less effective shorter. This means high-resolution...

13.5nm wavelength, CO₂-Sn-LPP EUV light source which is the most promising solution for capable of enabling high-volume-manufacturing semiconductor devices with critical layers patterned sub-10nm resolution. Our incorporates unique and original technologies such as; high power short pulse CO₂ laser, wavelength solid-state pre-pulse highly stabilized droplet generator, a laser-droplet shooting control system debris mitigation technology utilizing strong magnetic field....

A systematic approach to assigning aperture phases for the alternate-type phase-shift mask is proposed. Since requires a 180° phase difference between adjacent apertures, there possibility that conflicts will arise, thus requiring pattern design modification. As way make modification easier, this paper proposes novel algorithm successively apertures which are arranged in descending order of difficulty. Relative difficulty can be input by designer and/or calculated system from features. The...

The new method for enhancing the focus latitude in optical lithography, named FLEX (focus enhancement exposure) has been investigated. In imaging characteristics are greatly affected by several key parameters such as distance between adjacent focal planes and illuminator coherence factor. effect of these on image have examined using computer simulations. results simulations verified applying to sub-half-micron patterns a high numerical aperture i-line stepper. This confirmed validity...

We have been developing CO₂-Sn-LPP EUV light source which is the most promising solution as 13.5nm high power for HVM EUVL since 2003. Unique original technologies such as; combination of pulsed CO₂ laser and Sn droplets, dual wavelength pulse shooting mitigation with magnetic field developed in Gigaphoton Inc.. The theoretical experimental data clearly showed advantage our proposed strategy. demonstrated 117W (I/F clean burst), 50 kHz, 22 hours stable operation at...

A shifter placement program has been developed for alternate-type phase-shift masks that require a 180°-phase difference between adjacent aperture pairs. Using heuristic approach, this minimizes the number of phase conflicts arise when apertures are forced to have same phase. Adjacent relationships expressed by an undirected graph; found in closed loops containing odd apertures. Minimization is achieved listing these and identifying pairs occur more than one loop. The validity algorithm was...

A kinetic model for chemical amplification resist systems is proposed. This consists of photoacid generation step and acid‐catalyzed reactions promoted by both photon thermal energy. three‐component negative SAL601 (Shipley), exposed to a excimer laser, investigated determine validity the model. Assuming simple dissolution characteristics, can well explain exposure dose postexposure baking condition dependence cross‐linking photoabsorption characteristics this resist. Application profile...

A new photolithography technique called antireflective coating on resist (ARCOR) is described. This method improves linewidth accuracy and overlay by decreasing the multiple interference effect in a film. clear anti‐reflective film spun photoresist prior to alignment pattern detection exposure. The subsequently removed developed conventional way. Multiple reflection suppressed this film, thus enabling patterning without disturbance caused interference. With method, becomes 0.03 μm, about...