Microlithography in Semiconductor Device Processing

Publisher Summary This chapter presents the usage of microlithography in semiconductor device processing. The concerns of microlithographic processing are encompassed in the following items: resolution, pattern registration, dimensional control, cosmetic quality, and throughput of the machine. The term resolution refers to the ability to image two points of diminishing spacing. Pattern registration refers to the merging of two patterns so that they can fit to each other. The successful merging of all the patterns results in a pleasing photographic reproduction. The control refers to imaging the patterns on the wafer at the sizes contemplated by the device designer. The various components of the microlithographic process and the various categories of process quality are seen in relation to each other. The problems of wafer registration, CD control, and pattern resolution will be the areas of really exciting challenge in the next few years. Submicron patterning in the near future can be effectively done using the e-beam lithography (EBL). The problems facing EBL are developing proximity software that will not seriously prolong pattern writing times, getting the raster effects on CD variation under control, working out the details of a reasonable multilevel resist patterning scheme, and speeding the writing time by another order of magnitude.