Jong-Won Hong

Development of 38nm Bit-Lines using Copper Damascene Process for 64-Giga bits NAND Flash

In order to develop high density NAND flash device, the increased number of cell strings for 1 page buffer forces to form a long bit-line with low sheet resistance, as well as low parasitic capacitance between bit-lines. In this paper, we secured a copper damascene process to form 38 nm bit-lines with 76 nm pitch using SADP (self-aligned double patterning) process. The methods to minimize the sheet resistance and to suppress the parasitic capacitance were explained on NAND flash device with 38 nm node technology.

Optimization and Analysis of Low Voltage Phosphors Deposited Electrophoretically for the FED Applications

Low voltage phosphors for the application to prototype 4-inch full color field emission display devices was successfully deposited on indium-tin oxide (ITO) glasses by utilizing an electrophoretic method. The electrophoretic suspension used consisted of each color phosphor of 1 -3um size, isopropyl alcohol (IPA), charger and binder. The deposition rate of each color phosphor was systematically investigated by changing deposition time and applied voltages under conditions of various nitrate salts, such as Mg(N03)2, La(NO3)2 and AI(N03)2. The brightness of each deposited phosphor were analyzed both in the vacuum chamber and in fully-sealed environment. Experimental results significantly exhibit uniform thickness of about 4-9um thickness over the whole 4 inch glass plate, depending on electrical properties of each color phosphor.

Calculation of Vacuum Conditions Inside a FED using a Monte-Carlo Method

Vacuum properties of a field emission display (FED) device are calculated using a MonteCarlo method, The calculation is based on molecular flow conductance inside the FED panel with the exhausting pipe. This simulation result exhibits extremely low value of the conductance, resulting in pressure increase inside the panel by several orders of magnitude, even though large separation distance of the exhausting pipe is allowed, like few centimeters.