| 摘要 |
A method is provided for forming a uniformly salicided single crystal silicon emitter structure in a semiconductor integrated circuit bipolar transistor structure. The bipolar transistor structure includes a collector region that has a first conductivity type formed in a semiconductor substrate and a base region having a second conductivity type, opposite the first conductivity type, formed in the collector region. A layer of dielectric material is formed on the surface of the base region. An emitter window is opened in the layer of dielectric material to expose a surface area of the base region. A layer of polysilicon is then formed over the layer of dielectric material and extending into the emitter window such that at least a portion of the layer of polysilicon is in contact with the surface area of the base region. Dopant of the first conductivity type is then introduced into the layer of polysilicon. A region of anti-reflective coating (ARC) material is formed on the layer of polysilicon over the emitter window opening such that portions of the layer of polysilicon are exposed. Sufficient laser energy is then applied to the structure resulting from the foregoing steps to cause the polysilicon underlying the region of anti-reflective coating material to flow and recrystallize. The region of anti-reflective coating material is then utilized as a hard mask to remove unwanted regions of polysilicon, thereby defining a single crystal silicon emitter region under the ARC material and extending into the emitter window opening and in interfacial contact with the surface area of the base region. The ARC material is then removed and a layer of refractory metal silicide is formed on the recrystallized polysilicon emitter region.
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