Specific Process Knowledge/Thin film deposition/ALD Picosun R200: Difference between revisions
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[[image:ALD.jpg|300x300px|right|thumb|Picosun R200 ALD, positioned in cleanroom F-2.]] | [[image:ALD.jpg|300x300px|right|thumb|Picosun R200 ALD, positioned in cleanroom F-2.]] | ||
The Picosun R200 ALD (atomic layer deposition) tool is used to deposit a very thin layer of Al<sub>2</sub>O<sub>3</sub> | The Picosun R200 ALD (atomic layer deposition) tool is used to deposit a very thin layer of Al<sub>2</sub>O<sub>3</sub> or TiO<sub>2</sub> on different samples. | ||
Each process is using two different precurcors. The reaction takes place in cycles. During each cycle a very short pulse of each precursor is introduced into the ALD reaction chamber in turns, and in-between each precursor pulse the chamber is purged with nitrogen. All reactions have to take place on the sample surface, thus it is very important that each precurcor is removed from the chamber before the next one is introduced. In that way the ALD layer will be deposited atomic layer by atomic layer. | Each process is using two different precurcors. The reaction takes place in cycles. During each cycle a very short pulse of each precursor is introduced into the ALD reaction chamber in turns, and in-between each precursor pulse the chamber is purged with nitrogen. All reactions have to take place on the sample surface, thus it is very important that each precurcor is removed from the chamber before the next one is introduced. In that way the ALD layer will be deposited atomic layer by atomic layer. | ||
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The ALD reaction takes place under vacuum, thus a vacuum pump is connected to the bottom of the ALD reactor. The pump is located in the basement. | The ALD reaction takes place under vacuum, thus a vacuum pump is connected to the bottom of the ALD reactor. The pump is located in the basement. | ||
The liquid precursors (TMA, TiCl<sub>4 | The liquid precursors (TMA, TiCl<sub>4</sub> and H<sub>2</sub>O) are located in the cabinet below the ALD chamber. When the TMA and TiCl<sub>4</sub> precursors are not in use, the manual valves have to be closed. Ozone is generated by use of an ozone generator that is located on the side of the machine. | ||
It is possible to change the sample holder, so that ALD deposition can take place on different samples, e.g. a small wafer batch or a number of smaller samples. Samples are loaded manually into the sample holder by use of a tweezer. | It is possible to change the sample holder, so that ALD deposition can take place on different samples, e.g. a small wafer batch or a number of smaller samples. Samples are loaded manually into the sample holder by use of a tweezer. | ||