System and method for sputtering silicon films using hydrogen gas mixtures
AssigneeSharp Laboratories of America, Inc.
InventorApostolos Voutsas
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Abstract
A method has been provided for forming a polycrystalline silicon (p-Si) film with a small amount of hydrogen. Such a film has been found to have excellent sheet resistance, and it is useful in the fabrication of liquid crystal display (LCD) panels made from thin film transistors (TFTs). The low hydrogen content polycrystalline silicon films are made from introducing a small amount of hydrogen gas, with Ar, during the sputter deposition of an amorphous silicon film. The hydrogen content in the film is regulated by controlling the deposition temperatures and the volume of hydrogen in the gas feed during the sputter deposition. The polycrystalline silicon film results from annealing the low hydrogen content amorphous silicon film thus formed.
Claims27
In an integrated circuit (IC) fabrication process, a method for forming a polycrystalline silicon (p-Si) film, the method comprising:
- sputtering amorphous silicon (a-Si) material on a substrate;
- supplying a gas mixture including a hydrogen content of no more than 4% volume in the gas feed;
- and
- forming an amorphous silicon film incorporating hydrogen.
4 In an integrated circuit (IC) fabrication process, a method for forming a polycrystalline silicon (p-Si) film, the method comprising:
- sputtering amorphous silicon (a-Si) material on a substrate;
- supplying a gas mixture having a low hydrogen volume at the gas feed;
- and
- forming an amorphous silicon film incorporating no more than 4% hydrogen, by atomic weight.
The method of claim 4 further comprising:
- annealing the amorphous silicon film;
- and
- forming a polycrystalline silicon film having a crystalline content in the range from 95% to 100% and a hydrogen content in the range from 1 percent by atomic weight (at %) to 3 at %.
The method of claim 4 wherein sputtering amorphous silicon material on a substrate includes setting the process temperature in the range from 200 degrees C. to 400 degrees C.
In an integrated circuit (IC) fabrication process, a method for forming a polycrystalline silicon (p-Si) film, the method comprising:
- sputtering amorphous silicon (a-Si) material on a substrate;
- supplying a gas mixture including no more than 4% hydrogen volume in the gas feed;
- forming an amorphous silicon film incorporating no more than 4% hydrogen, by atomic weight.
In the fabrication of a thin film transistor (TFT), a polysilicon (p-Si) film comprising:
- a pre-anneal amorphous silicon (a-Si) film having a content of no more than 4% hydrogen, by atomic weight;
- and
- a post-anneal polycrystalline silicon film having a crystalline content in the range from 95% to 100%, and a hydrogen content in the range from 1 percent by atomic weight (at %) to 3 at %.
In the fabrication of a thin film transistor (TFT), a pre-anneal film comprising:
- amorphous silicon (a-Si);
- and
- no more than 4% hydrogen content in the amorphous silicon, by atomic weight.
In the fabrication of a liquid crystal display (LCD) including a thin film transistor (TFT), a polysilicon (p-Si) film comprising:
- a pre-anneal amorphous silicon (a-Si) film having a content of no more than 4 percent by atomic weight (at %) hydrogen;
- and
- a post-anneal polycrystalline silicon film having a crystalline content in the range from 95% to 100% and a hydrogen content in the range from 1 percent by atomic weight (at %) to 3 at %.
Dependencies are inferred from the claim text.