摘要 |
A recess having a height-to-width aspect ratio from about 6:1 to about 10:1 in a semiconductor structure is taught with a method of forming the same. In a first embodiment, a refractory metal layer is formed in the recess, which can be a trench, a contact hole, or a combination thereof. A refractory metal nitride layer is then formed on the refractory metal layer. A heat treatment is used to form a metal silicide contact at the bottom of the contact hole upon a semiconductor material. In a first alternative method, an ammonia high-temperature treatment is conducted to remove undesirable impurities within the refractory metal nitride layer lining the contact hole and to replace the impurities with more nitrogen. In a second alternative method, a second refractory metal nitride layer is formed by PVD upon the first refractory metal nitride layer. In either alternative, a metallization layer is deposited within the recess. High pressure and temperature are used to substantially fill the recess with the metallization layer. Following the substantially filling of the recess, residual surface metallization may at least be partially removed by techniques such as etch back or CMP.
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