Conclusions Nanopillar array has been successfully obtained on a spin-coated thin film of OIR906 photoresist, employing a kind of novel visible CW laser direct lithography

system. The diameter of the fabricated nanopillar was able to be as small as 48 nm, which is 1/11 of the wavelength of the incident CT99021 nmr laser. The lithographic nanopatterns were calibrated and analyzed with AFM. Shape influences of the coma effect and astigmatism effect were simultaneously analyzed using vector integral. The simulation results explain the distortion and inconsistency of the fabricated nanopatterns well. The work has demonstrated a simple, efficient, and low-cost method of fabricating nanopillars. It could pave a new way to PD0332991 fabricate nanopillars/pore arrays of large area distribution for optical nanoelements and biophotonic sensors

while integrated with high-speed scanning system. Appendix Aberration theory about high NA objective Figure 8 is a schematic for laser spot distribution on a focal plane. The Gaussian beam is converted clockwise, is polarized by WP, and then passes through the PP and incident into the high NA objective lens. The components of the diffracted electric field at point P, which is near to the focal spot, can be expressed by the vectorial Debye theory as in Equation 1 [32]: (1) where f is the focal length of the lens and l 0 represents the amplitude factor in the image space; E 0 is the amplitude of input Gaussian beam; A 1(θ, ϕ) is the wavefront aberration function,

θ is the angle between the optical axis and given ray; ϕ is the azimuthal coordinate at the input plane and φ s (θ, ϕ) is the phase click here delay generated by the phase mask; x, y, and z indicate the Cartesian coordinates of the point p in the focal region; i is the plural; k = 2πn/λ stands for the wave number, where λ is the wavelength of the incident light and n is the refractive index of the focal space medium. Figure 8 Schematic drawing of light intensity distribution on the focal plane. The amplitude of the Gaussian beam at the input plane is expressed as in 4��8C Equation 2: (2)where A 0 is the amplitude, γ is the truncation parameter and expressed as γ = a/ω (a is the aperture radius and ω is the beam size at the waist), while ρ stands for the radial distance of a point from its center normalized by the aperture radius of the focusing system and ρ = sinθ/sinθ max, where θ max is the maximal semi-aperture angle of the objective lens, and in our system, θ max = 67.07°. A 1(θ, ϕ) represents wavefront aberration as expressed as in Equations 3 and 4: Coma: (3) Astigmatism: (4) A c and A a are coefficients for coma and astigmatism, respectively. Both A c and A a multiply λ, representing the departure of the wavefront at the periphery of the exit pupil. The values for λ, n, NA and θ max adopted in simulation correspond to the practical values in the experiment. Refractive index of oil n = 1.