Abstract: The present invention includes a method and apparatus for the rapid, nondestructive evaluation of the contrast of a latent image in a photoresist. More particularly, the contrast of the latent image is directly monitored by measuring the intensity of the light diffracted from a pattern in the exposed, undeveloped photoresist known as the latent image. The proper exposure tool parameters, such as exposure tool time and focus, is suitably determined based on the intensity of different orders of diffracted light, namely the 2nd-order diffracted from the latent image. In a preferred embodiment, a test pattern consisting of a periodic pattern, or a pattern of the device associated with the particular lithographic step, is employed to provide well-defined diffraction orders.

Abstract: An optical scatterometer system enables illumination of a sample material at various angles of incidence without rotating or otherwise moving the sample material.

Abstract: In microelectronics manufacturing, an arrangement for monitoring and control of exposure of an undeveloped photosensitive layer on a structure susceptible to variations in optical properties in order to attain the desired critical dimension for the pattern to be developed in the photosensitive layer.

Abstract: For critical dimension (CD) metrology of photomasks, a laser scatterometer linewidth measurement tool provides noncontact rapid, and nondestructive measurement of linewidth. Calculation of the linewidth is based on a rigorous theoretical model, thus eliminating the need for calibrations. A chrome-on-glass diffraction grating is illuminated with a laser. A photodetector mounted behind the photomask measures the scattered power in each diffracted order. This provides data for the rigorous theoretical model which provides a relationship between the linewidth of the photomask grating and the fraction of total power diffracted into the transmitted zero-order. This scatterometer linewidth measurement technique provides a simple, rapid, nondestructive, and noncontact method of linewidth determination which takes into account the effect of the glass substrate on which the grating is placed.