| 摘要 |
PURPOSE:To improve the value of the junction depth of an ultrafine region and a surface sheet resistance value by comparing the diffusion from a mask hole of ultrafine size with other wide region to increase the amount of implanting impurity. CONSTITUTION:In a method of forming a junction by implanting a conductive impurity different from the conductivity of a semiconductor substrate through a mask having ultrafine holes of less than 1.0mum and holes sufficiently larger than the ultrafine holes on the substrate, impurities of the number represented by the product of surface density (1/cm<2>), diffusion coefficient (cm<2>/sec) and diffusing time (sec) of the impurities in the ultrafine holes in advance before the diffusing step are additionally implanted. The forming junction depth (xj) and surface sheet resistance value (rhos) are the same as (xj) and (rhos) in the sufficiently wide region through diffusing step of implanting the impurities from a mask window of very small size.
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