Example embodiments of inventive concepts generally relate to semiconductor devices, and more particularly, to semiconductor devices including a vertical channel transistor and/or to methods of fabricating the same.
Due to their small-sized, multifunctional, and/or low-cost characteristics, semiconductor devices are used in the electronic industry. Higher integration of semiconductor memory devices is desired to satisfy consumer demands for superior performance and inexpensive prices. In the case of semiconductor memory devices, increased integration is desired because integration can affect product prices. However, the process equipment for increasing pattern fineness may be expensive and can set a practical limitation on increasing integration for semiconductor memory devices.
New technology is being studied for increasing the integration density of semiconductor memory devices. For example, a semiconductor memory device may include a vertical transistor having a vertical channel and source and drain regions vertically spaced apart from each other by the vertical channel. However, for the vertical transistor, the source or drain region may be interposed between the vertical channel and a substrate, such that the vertical channel is in a floated state. The floating of the vertical channel may lead to an accumulation of holes in the vertical channel and/or a formation of subthreshold and/or parasitic bipolar junction transistor. Furthermore, for example, in a dynamic random access memory (DRAM), this may result in a leakage current between a capacitor node and a bit line node and deteriorate a data retention property of memory cell.