| 摘要 |
PURPOSE:To avoid discontinuity by the step in an interconnection by a method wherein, after a lower layer interconnection is formed on a foundation insulating film formed on a semiconductor substrate, a layer insulating film, thicker than the lower layer interconnection, is formed on the foundation insulating film and, after a photoresist film with a reversal pattern of the lower layer interconnection is formed on the layer insulating film, the protruding parts of the layer insulating film are etched. CONSTITUTION:The 1st layer interconnection 13 is formed on an SiO2 film 12 formed on a semiconductor substrate 11 and an SiO2 film 14, as a layer insulating film, is formed on the SiO2 film 12 including the 1st layer interconnection 13 so as to be thicker than the 1st layer interconnection 13. Then, after negative type photoresist 15, whose exposed part is left, is applied by spin-coating, the photoresist is exposed and developed with a photolithography mask used for forming the 1st layer interconnection 13. With this process, the photoresist 15 remains on the SiO2 film 14 with the reversal pattern of the 1st layer interconnection 13. After that, the protruding parts 14a is removed by etching with the remaining photoresist 15 as a mask to make the surface of the SiO2 film 14 flat. Then, after the photoresist 15 is removed, the 2nd layer interconnection 16 is formed with Al on the SiO2 film 14. With this constitution, a discontinuity of the upper layer interconnection caused by a step can be avoided.
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