Specific Process Knowledge/Thin film deposition/ALD2 (PEALD): Difference between revisions
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The liquid precursor sources TMA, TiCl<sub>4</sub> and H<sub>2</sub>O are stored in bottles located in a side cabinet on the left side of the machine. When the TMA and TiCl<sub>4</sub> precursors are not in use, the manual valves have to be closed. The powder precursors SAM24 and TEMAHf are stored in bottles located in a big cabinet below the ALD chamber. These precursors are heated by heating jackets, and users should not open and close the manual valves. O3 is generated by use of an ozone generator that is located in the E-rack at the right side of the machine. | The liquid precursor sources TMA, TiCl<sub>4</sub> and H<sub>2</sub>O are stored in bottles located in a side cabinet on the left side of the machine. When the TMA and TiCl<sub>4</sub> precursors are not in use, the manual valves have to be closed. The powder precursors SAM24 and TEMAHf are stored in bottles located in a big cabinet below the ALD chamber. These precursors are heated by heating jackets, and users should not open and close the manual valves. O3 is generated by use of an ozone generator that is located in the E-rack at the right side of the machine. | ||
A remote plasma generator is connected to the upper part of the reactor chamber. Different precursor gases are connected to this plasma generator through the same gas inlet | A remote plasma generator is connected to the upper part of the reactor chamber. Different precursor gases are connected to this plasma generator through the same gas inlet. At the moment the available plasma precursor gases are N<sub>2</sub>, O<sub>2</sub> and NH<sub>3</sub>, and soon H<sub>2</sub>/N<sub>2</sub> will also be available. The plasma gas inlet is constantly purged with argon. The plasma gasses can also be used as precursors for thermal ALD if the power to the plasma generator is not turned on. | ||
The plasma generator is separated from the reactor chamber by a plasma cone (or chamber lid). The argon flow through the plasma gas inlet ensures that the plasma cone remains clean. | The plasma generator is separated from the reactor chamber by a plasma cone (or chamber lid). The argon flow through the plasma gas inlet ensures that the plasma cone remains clean. | ||
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The precursor pulse time is controlled by special ALD valves that allow very short precursor pulses to be introduced into the ALD reactor chamber and at the same time allow a constant nitrogen or argon flow. Thus, nitrogen and argon are always flowing through the ALD valves into the chamber, independent on whether a precursor pulse is introduced or not. | The precursor pulse time is controlled by special ALD valves that allow very short precursor pulses to be introduced into the ALD reactor chamber and at the same time allow a constant nitrogen or argon flow. Thus, nitrogen and argon are always flowing through the ALD valves into the chamber, independent on whether a precursor pulse is introduced or not. | ||
At the moment it is possible to deposit Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, HfO<sub>2</sub>, SiO<sub>2</sub>, AlN and TiN in the ALD | At the moment it is possible to deposit Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, HfO<sub>2</sub>, SiO<sub>2</sub>, AlN and TiN in the ALD. In order to deposit good quality nitride layers with low sheet resistance, the amount of oxygen has to be very low. Thus, the ALD reactor chamber has to be passivated before nitride depositions can be done, and oxides and nitrides cannot be deposited at same time. | ||
Samples are loaded through a load lock. 6" and 8" wafers can be loaded directly in the load lock, while 4" wafers and smaller samples have to be placed on a 6" carrier plate or a 6" silicon dummy wafer with an etched recess. It is only possible to load one wafer or carrier plate at a time by use of the load lock. | Samples are loaded through a load lock. 6" and 8" wafers can be loaded directly in the load lock, while 4" wafers and smaller samples have to be placed on a 6" carrier plate or a 6" silicon dummy wafer with an etched recess. It is only possible to load one wafer or carrier plate at a time by use of the load lock. | ||
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The ALD is controlled by use of a computer with a touch screen that is situated next to the machine. | The ALD is controlled by use of a computer with a touch screen that is situated next to the machine. | ||
A short presentation with some information about the ALD tool can be found [[Media:ProcessMeeting ALD 2013-12-06_1.pdf|here]]. | A short presentation with some information about the ALD tool can be found [[Media:ProcessMeeting ALD 2013-12-06_1.pdf|here]]. | ||