METHOD OF FORMING TAPERED HOLE THROUGH INSULATING LAYER IN ORDER TO FORM CONTACT INTO INTEGRATED DEVICE

摘要

PURPOSE: To form a tapered hole by anisotropically etching an insulation layer by a depth smaller than the thickness of a first insulation layer through a mask in RIE plasma and by anisotropically etching a second insulation material layer in the RIE plasma without masking. CONSTITUTION: A photoresist mask 6 is formed, reactive ion etching (substantially anisotropic etching) is continued until the layer of about 1000-2000Åof an insulation material 5 remains on the bottom part of an etched hole, and the remaining layer of the masking photoresist 6 is removed. Then, the second insulation layer 7 is stuck by the thickness of about 4500-6000Åso as to be substantially suited. Second RIE plasma etching is applied to the second insulation material layer 7 and continued until the remaining layer of the insulation material 5 remaining on the bottom part of the previously etched hole is completely removed. Thus, the remaining part 7' is left on the wall surface in a vertical direction of the hole, so that the desired tapered hole for a contact point can be formed.