Method of manufacturing a semiconductor device and a semiconductor manufacture system
View Patent ↗This invention makes it possible to make even films composed of at least silicon and germanium with gradient germanium ratio along a film thickness direction thereof for a short deposition time. A temperature controller 61 controls a heater 2 so that temperature of wafers W will be changed from low (e.g. 400° C.) to high (e.g. 700° C.) by alternately repeating temperature changing process to heat up the wafers W and temperature regulating process when temperature of the wafers W does not change as much as that of the temperature changing process for a specific amount of time. While a gas controller 62 provides a reactive gas into a reaction tube 1 during the temperature regulating process, it controls a valve 31 to stop it during the temperature changing process.
1. A method of manufacturing a semiconductor device by depositing films being composed of at least silicon and germanium on a substrate or substrates collocated in a reaction chamber so that a ratio of the germanium composition is changed along a film thickness direction thereof, the method comprising:
changing a temperature of the substrate or the substrates from high to low or from low to high, wherein changing the temperature comprises repeatedly performing:
a temperature changing process in which the temperature of the substrate or the substrates is changed, and
a temperature regulating process in which temperature of the substrate or the substrates is stabilized;
depositing said films composed of at least said silicon and germanium by providing a reactive gas which contains silicon and germanium into the reaction chamber during the temperature regulating process; and
processing the substrate or the substrates by lowering partial pressure of the reactive gas during the temperature changing process than during the temperature regulating process.
2. The method of manufacturing the semiconductor device according to claim 1 , wherein
the temperature regulating process is a process for maintaining a constant temperature of the substrate or the substrates.
3. The method of manufacturing the semiconductor device according to claim 1 , wherein
the temperature changing process is a process for exhausting the reactive gas remaining in the reaction chamber.
4. The method of manufacturing the semiconductor device according to claim 1 , wherein
the reactive gas comprises a first reactive gas which contains silicon and a second reactive gas which contains germanium; and
the temperature regulating process is a process to change in sequence or in phase partial pressure of the second reactive gas in the reaction chamber.
5. A method of manufacturing a semiconductor device by depositing films being composed of at least silicon and germanium on a substrate or substrates collocated in a reaction chamber so that a ratio of the germanium composition is changed along a film thickness direction thereof, the method comprising:
changing a temperature of the substrate or the substrates from high to low or from low to high, wherein changing the temperature comprises repeatedly performing:
a temperature changing process in which the temperature of the substrate is changed, and
a temperature regulating process in which the temperature of the substrate or the substrates is stabilized;
depositing said films composed of at least said silicon and germanium by providing a reactive gas which contains silicon and germanium into the reaction chamber during the temperature regulating process; and
processing the substrate or the substrates by lowering the flow rate of the reactive gas during the temperature changing process than during the temperature regulating process.
6. The method of manufacturing the semiconductor device according to claim 1 , wherein
said films are not substantially deposited on the substrate or the substrates during the temperature changing process.
7. The method of manufacturing the semiconductor device according to claim 1 , wherein
the reactive gas comprises a first reactive gas which contains silicon and a second reactive gas which contains germanium; and
the temperature regulating process is a process to change in phase partial pressure of the second reactive gas in the reaction chamber, and to change deposition time at each of the above-mentioned phases.
8. The method of manufacturing the semiconductor device according to claim 7 , wherein
the deposition time is the time when the film thickness at each of the above-mentioned phase is almost the same.
9. The method of manufacturing the semiconductor device according to claim 1 , wherein
a base layer is deposited in the semiconductor device that contains lamination structure comprising a collector layer, the base layer, and an emitter layer.
10. A semiconductor manufacture system for depositing films composed of at least silicon and germanium on a substrate or substrates collocated in a reaction chamber so that a ratio of the germanium composition is changed along a film thickness direction thereof, the system comprising:
a temperature controller which changes a temperature of the substrate or the substrates from high to low or from low to high, wherein the temperature controller changes the temperature by repeatedly performing:
a temperature changing process for changing the temperature of the substrate or the substrates and
a temperature regulating process in which the temperature of the substrate or the substrates is stabilized; and
a gas controller which provides a reactive gas which contains silicon and germanium into the reaction chamber during the temperature regulating process, as well as for lowering partial pressure of the reactive gas during the temperature changing process than that during the temperature regulating process.