Methods of forming silicon quantum dots and methods of fabricating semiconductor memory devices using the same
View Patent ↗Techiques for forming a silicon quantum dot, which can be applied to the formation of a semiconductor memory device, are disclosed. The techniques may include depositing a first dielectric layer on a semiconductor substrate, depositing a polysilicon layer on the first dielectric layer, forming a plurality of metal clusters on the polysilicon layer in regular distance, and etching the polysilicon layer using the plurality of metal clusters as a mask. As disclosed herein, it is possible to form the silicon quantum dots having the fineness and uniformity characteristic together with the single crystalline level characteristic.
1. A method for fabricating a semiconductor memory device comprising:
defining an active region and non-active region using a device isolation layer formed on a semiconductor substrate;
depositing a first dielectric layer on the active region;
depositing a polysilicon layer on the first dielectric layer;
forming a plurality of metal clusters on the polysilicon layer;
forming separated silicon quantum dots by etching the polysilicon layer using the plurality of metal clusters at regular intervals as a mask until a top surface of the first dielectric layer is exposed;
removing the plurality of metal clusters;
depositing a second dielectric layer on the separated silicon quantum dots;
forming a conductive layer for gate electrodes on the second electric layer; and
removing the conductive layer and the first and second dielectric layers selectively.
2. The method as defined by claim 1 wherein each of the plurality of metal clusters comprises gold, silver, or a transition metal.
3. The method as defined by claim 1 wherein the polysilicon layer has a thickness in the range of 10 to 100 nanometers.