Methods of fabricating vertical field effect trans

专利名称：Methods of fabricating vertical field effect

transistors by conformal channel layerdeposition on sidewalls

发明人：Zhibo Zhang申请号：US10007895申请日：20011106公开号：US06664143B2公开日：20031216

专利附图：

摘要：Vertical field effect transistors are fabricated by depositing a vertical channel ona microelectronic substrate at a thickness along the microelectronic substrate that is

independent of lithography, the vertical channel extending orthogonal to the

microelectronic substrate. Source and drain regions are formed at respective oppositeends of the vertical channel, and an insulated gate is formed adjacent the vertical channel.More specifically, a first doping layer is formed on a microelectronic substrate, anintermediate layer is formed on the first doping layer opposite the substrate and asecond doping layer is formed on the intermediate layer opposite the first doping layer.A trench is then formed in the first doping layer, the intermediate layer and the seconddoping layer, the trench including a trench sidewall. The trench sidewall is lined with aconformal amorphous silicon layer. The conformal silicon layer on the trench sidewallincludes a first end portion adjacent the first doping layer, a second end portion adjacentthe second doping layer, and a middle portion between the first and second end portionsadjacent the intermediate layer. The amorphous silicon layer is then crystallized. Thetrench that is lined is plugged, for example with high dielectric constant material.Annealing is performed to dope the first end portion and the second end portion withdopants from the first and second doping layers respectively. The intermediate layer isremoved adjacent the middle portion to expose at least some of the middle portion. Agate insulating layer is formed on the middle portion that is exposed, and a gateelectrode is formed on the gate insulating layer, opposite the middle portion. One ormore drain contacts may be formed in the microelectronic substrate prior to forming thefirst doping layer, for example using silicide. Moreover, one or more source contacts maybe formed on the second end of the conformal silicon layer.

申请人：NORTH CAROLINA STATE UNIVERSITY

代理机构：Myers Bigel Sibley & Sajovec

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