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With the adoption of extreme ultraviolet (EUV) lithography for high volume production in the advanced wafer manufacturing fab, defects resulting from stochastic effects could be one of major yield killers and draw increasing interest from the industry. In this paper, we will present a flow, including stochastic edge placement error (SEPE) model calibration, pattern recognition and hot spot ranking from defect probability, to detect potential hot spot in the chip design. The prediction result shows a good match with the wafer inspection. HMI eP5 massive metrology and contour analysis were used to extract wafer statistical edge placement distribution data.

All chipmakers understand that variability is the enemy of any process and that defectivity reduction is essential to improving yield which translates to profit. Aggressive process window and yield specifications put tight requirements on the DUV light source which will impact scanner imaging performance. Accurate identification of defectivity caused by on wafer hotspots along with the impact on process windows can be accomplished using existing industry capability. ASML’s Brion Lithography Manufacturing Checker (LMC) can be employed using existing models to perform hotspot analysis and verify process window impact for current and future 193 nm nodes. In this presentation, we review a methodology to understand the effect bandwidth variation has on hotspot variability and defect variation on specific customer designs. Initial studies are based on a large number of customer specific 90 nm pitch layouts where bandwidth variability is investigated for its impact on hotspot variability. Defect density maps are generated from the baseline process with additional maps generated at various bandwidth ranges. This methodology has been applied to Cymer’s DynaPulse and new DynaPulse2 bandwidth control technologies demonstrating the impact that bandwidth variation can influence process defectivity levels.

Demand for mask process correction (MPC) is growing for leading-edge process nodes. MPC was originally intended to correct CD linearity for narrow assist features difficult to resolve on a photomask without any correction, but it has been extended to main features as process nodes have been shrinking. As past papers have observed, MPC shows improvements in photomask fidelity. Using advanced shape and dose corrections could give more improvements, especially at line-ends and corners. However, there is a dilemma on using such advanced corrections on full mask level because it increases data volume and run time. In addition, write time on variable shaped beam (VSB) writers also increases as the number of shots increases. Optical proximity correction (OPC) care-area defines circuit design locations that require high mask fidelity under mask writing process variations such as energy fluctuation. It is useful for MPC to switch its correction strategy and permit the use of advanced mask correction techniques in those local care-areas where they provide maximum wafer benefits. The use of mask correction techniques tailored to localized post-OPC design can result in similar desired level of data volume, run time, and write time. ASML Brion and NCS have jointly developed a method to feedforward the care-area information from Tachyon LMC to NDE-MPC to provide real benefit for improving both mask writing and wafer printing quality. This paper explains the detail of OPC care-area feedforwarding to MPC between ASML Brion and NCS, and shows the results. In addition, improvements on mask and wafer simulations are also shown. The results indicate that the worst process variation (PV) bands are reduced up to 37% for a 10nm tech node metal case.

We report improvements on a technique for measuring the complex chi(3) of nonlinear polymers using a 2D phase grating and degenerate four wave mixing. These improvements produce a factor of 100 increase in the signal to noise ratio.

Transient dynamics of photoexcited carriers in MEH-PPV, PCBM-C60 and their blend is investigated by THz-TDS using a 400 nm optical pump and terahertz probe. Free and bound carriers are revealed in the measurement of the complex conductivity.

Transient optical and electronic properties of photoexcited, semiconductor (p-type silicon) and semiconducting polymer (MEH-PPV/PCBM) are measured by terahertz time-domain spectroscopy using a 400 nm optical pump and terahertz probe. The semiconductor data is fit using a simple Drude model. The semiconducting polymer data shows very fast carrier rise time and decay time

Photoconductivity, photo-carrier density and lifetime in MEH-PPV were obtained by direct measurement of photo-conductivity and photo-induced change in reflectivity. Fast transient carrier mobility of 800 (cm2/Vs) and quantum efficiency of 0.5% were estimated.

Terahertz time-domain spectroscopy was used as a non-contact method to measure theconductivity of an ITO film and a photoexcited MEH-PPV film. The experimental data from ITO measurement were fit and agree with a Drude relationship. Article not available.

THz radiation power dependence on pump laser spot size was explored using a poled polymer and the electro-optic coefficient of the polymer was estimated. THz spectroscopy on several UV-curable passive polymers was also carried out.

We report progress in the development of polymer waveguides and devices for photonic applications in three areas: non-photolithographic techniques for polymer waveguide fabrication, bistability in laterally-coupled polymer microring resonators, and ultrafast photoconductive switches fabricated from semiconducting polymers. The non-photolithographic techniques for waveguide fabrication under development include laser milling with an excimer laser and programmable automatic dispensing of multimode polymer waveguides using an Essemtech automatic dispenser. Asymmetric diffraction gratings fabricated using phase masks and the interference of two excimer laser beams have exhibited concentration of optical power into the 1st diffraction order. Polymer micro-ring resonators laterally coupled to a bus line were fabricated by lithography from benzocyclobutene with radii as small as 10 μm and free spectral ranges on the order of 20 nm. These devices exhibit bistability in the frequency domain which can arise from thermal or nonlinear optical changes in refractive index and that may have application for all-optical switching. Metal-polymer-metal switches fabricated with interdigitated electrodes in an inverted structure exhibited fast transient photoconductive pulsewidths under 20 ps in response to femtosecond pump laser pulses, but the measurement was bandwidth limited by the oscilloscope. Here we report pump-probe measurements that indicate carrier lifetimes on the order of 2 ps.

Dual-Sided LCD displays are ideally suited for the public information display (PID) application. The UV excited flat lighting (UFL) was successfully demonstrated to perform dual-Sided illumination with the features of flat lighting, uniform luminance and high brightness on a 42” TFT-LCD display. Compared to conventional CCFL or LED lighting source, UFL is superior for the dual-Sided display application with its slim backlight module profile and power saving.

We present a simple optical arrangement for phase sensitive detection of degenerate four-wave mixing (DFWM) to characterize the real and imaginary parts of Chi((3)) using an imaged 2-D phase grating. Phase sensitive coherent detection of DFWM signal is demonstrated. Phase stabilization of the interferometric arms is obtained passively with the 2-D grating. A processable polyacetylene sample is characterized at a wavelength of 1.5 microm using this technique. The observed nonlinearity is determined to be a fast (250 fs) effect using a simple test.

A new laser lithography technique using the effect of optical superresolution can effectively reduce the exposed spot size on a photoresist layer, thus allowing disk mastering toward higher density using an existing light source and optics. A thin metallic mask layer deposited on the top of the photoresist layer is used to obtain a “below optical diffraction limit” linewidth on the photoresist layer. The feasibility of the laser lithography technique, as evaluated by simulation and experimental results, revealed that the linewidth on the photoresist layer could be shrunk by more than 50% of the diffraction limit of the optical system.