摘要 |
A multilevel metallization process which allows fabrication of several types of high density MOS and bipolar integrated circuits. The process uses a pad located under the inter-layer contact opening. The material of the pad is poly-silicon (doped or undoped), a refractory metal, or a refractory metal silicide which is not capable of being attacked during chemical etching of the metallization layers. If poly-silicon is used, it is either doped during its deposition or during contact doping, or it is automatically silicided during ohmic and Schottky contact formations.
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