Method for manufacturing semiconductor element and deposition apparatus

Abstract

An object of the present invention is to provide an apparatus for successive deposition used for manufacturing a semiconductor element including an oxide semiconductor in which impurities are not included. By using the deposition apparatus capable of successive deposition of the present invention that keeps its inside in high vacuum state, and thus allows films to be deposited without being exposed to the air, the entry of impurities such as hydrogen into the oxide semiconductor layer and the layer being in contact with the oxide semiconductor layer can be prevented; as a result, a semiconductor element including a high-purity oxide semiconductor layer in which hydrogen concentration is sufficiently reduced can be manufactured. In such a semiconductor element, off-state current is low, and a semiconductor device with low power consumption can be realized.

What is claimed is: 
     
         1 . A deposition apparatus comprising:
 a load lock chamber connected to a unit capable of evacuating the load lock chamber to have a pressure of 10 −6  Pa or less;   a plurality of deposition chambers each being connected to a unit capable of evacuating the deposition chamber to have a pressure of 10 −8  Pa or less;   a heating chamber connected to a unit capable of evacuating the heating chamber to have a pressure of 10 −8  Pa or less; and   a transfer chamber connected to the load lock chamber, the heating chamber, and the plurality of deposition chambers through gate valves and connected to a unit capable of evacuating the transfer chamber to have a pressure of 10 −6  Pa or less.   
     
     
         2 . The deposition apparatus according to  claim 1 , wherein the units capable of evacuating the load lock chamber, the heating chamber, the plurality of deposition chambers, and the transfer chamber are entrapment pumps. 
     
     
         3 . The deposition apparatus according to  claim 1 , wherein the amount of leakage of the air from the deposition chamber is 10 −11  Pa·m 3 /s or less. 
     
     
         4 . The deposition apparatus according to  claim 1 , further comprising a treatment chamber provided with a unit capable of generating oxygen radical and a unit capable of evacuating the treatment chamber to have a pressure of 10 −8  Pa or less. 
     
     
         5 . The deposition apparatus according to  claim 1 , wherein the heating chamber has a unit capable of heating at room temperature to 700° C. inclusive. 
     
     
         6 . A deposition apparatus comprising:
 a load lock chamber connected to a unit capable of evacuating the load lock chamber to have a pressure of 10 −6  Pa or less;   a plurality of deposition chambers each including a substrate holding portion provided with a first heating unit for heating a substrate and a second heating unit for heating a wall surface of a periphery of the substrate holding portion, and each being connected to a unit capable of evacuating the deposition chamber to have a pressure of 10 −8  Pa or less;   a heating chamber connected to a unit capable of evacuating the heating chamber to have a pressure of 10 −8  Pa or less; and   a transfer chamber connected to the load lock chamber, the heating chamber, and the plurality of deposition chambers through gate valves and connected to a unit capable of evacuating the transfer chamber to have a pressure of 10 −6  Pa or less.   
     
     
         7 . The deposition apparatus according to  claim 6 , wherein the units capable of evacuating the load lock chamber, the heating chamber, the plurality of deposition chambers, and the transfer chamber are entrapment pumps. 
     
     
         8 . The deposition apparatus according to  claim 6 , wherein at least one of the plurality of deposition chambers is provided with a target holding portion for fixing a target. 
     
     
         9 . The deposition apparatus according to  claim 6 , wherein the amount of leakage of the air from the deposition chamber is 10 −11  Pa·m 3 /s or less. 
     
     
         10 . The deposition apparatus according to  claim 6 , wherein the first heating unit is a unit capable of heating the substrate at room temperature to 500° C. inclusive. 
     
     
         11 . The deposition apparatus according to  claim 6 , further comprising a treatment chamber provided with a unit capable of generating oxygen radical and a unit capable of evacuating the treatment chamber to have a pressure of 10 −8  Pa or less. 
     
     
         12 . The deposition apparatus according to  claim 6 , wherein the heating chamber has a unit capable of heating at room temperature to 700° C. inclusive.