Forming a thin film structure

1. A method of forming a microcrystalline thin film, comprising:

supplying, during a first process, SiH 4 and H 2 to a chamber in which a substrate is located;

during the first process, applying an electric field to break down the SiH 4 to SiH 2 ;

supplying, during a second process, H 2 but not SiH 4 to the chamber;

depositing a portion of the microcrystalline thin film during the second process, wherein depositing the portion comprises adsorbing the Sill 2 to a surface of the substrate to form microcrystals, and wherein the portion of the microcrystalline thin film is formed without converting amorphous silicon to the microcrystals; and

performing the first process and second process a plurality of times to form the microcrystalline thin film having a target film thickness on the substrate.

2. The method of claim 1 , wherein performing the first process and second process a plurality of times is performed without removing the substrate from the chamber.

3. A method of forming a microcrystalline thin film, comprising:

supplying, during a first process, SiH 4 and H 2 to a chamber in which a substrate is located;

supplying, during a second process, H 2 but not SiH 4 to the chamber;

depositing a portion of the microcrystalline thin film during the second process; and

performing the first process and second process a plurality of times to form the microcrystalline thin film having a target film thickness on the substrate,

wherein supplying SiH 4 and H 2 during the first process comprises supplying SiH 4 at a first rate and H 2 at a second rate, the first rate and second rate defining a flow rate ratio that prevents a thin film formed on the substrate from becoming amorphous.

4. The method of claim 3 , further comprising applying an electric field in the chamber to break down the SiH 4 to SiH 2 .

5. The method of claim 4 , wherein supplying the H 2 comprises supplying the H 2 at a generally constant rate.

6. The method of claim 4 , further comprising depositing the SiH 2 to a surface of the substrate during the second process.

7. The method of claim 3 , further comprising:

converting SiH 4 to SiH 2 ; and

depositing SiH 2 on the substrate during the second process.

8. The method of claim 7 , wherein depositing SiH 2 on the substrate during the second process without supplying SiH 4 reduces formation of a polymer clue to SiH 2 molecules encountering each other prior to depositing of SiH 2 on the substrate.

9. The method of claim 3 , further comprising applying an electric field during the first process, the electric field set at an intensity that in combination with the flow rate ratio prevents a thin film formed on the substrate from becoming amorphous.

10. A method of forming a niicrocrystalline thin film by activating SiH 4 , and forming a film having a inicrocrystalline structure on a film forming target object, wherein activating SiH 4 comprises applying an electric field to break down SiH 4 to SiH 2 , the method further comprising:

performing a source supplying process in which SiH 4 is supplied,

performing a source depositing process in which the supply of SiH 4 is stopped and SiH 2 is deposited on the film forming target object to form the microcrystalline structure, and

supplying H 2 during the source supplying process and during the source depositing process, SiH 4 and H 2 being supplied at flow rates during the source supplying process to prevent a film formed on the film forming target object from becoming amorphous.

11. The method of claim 10 , wherein bonding of SiH 2 is suppressed in the source depositing process.

12. The method of claim 10 , wherein H 2 is supplied at a constant flow rate throughout said source supplying process and said source depositing process.

13. The method of claim 10 , wherein a flow rate ratio, r, of SiH 4 and H 2 satisfies r≧−(7/12)×P+72.5, where P is an electric field intensity density irradiated on SiH 4 and H 2 .

14. The method of claim 10 , wherein performing said source supplying process comprises performing the source supplying process for 2 seconds or less, and performing said source depositing process comprises performing said source depositing process for longer than said source supplying process.

15. A method of manufacturing a thin film transistor comprising:

forming a gate electrode on the substrate;

forming an insulation layer film on said substrate and said gate electrode,

forming at least a portion of a channel layer film on said insulation layer by using the microcrystalline thin film forming method of claim 10 ; and

forming a source/drain electrode on said channel layer.

16. The method of manufacturing a thin film transistor of claim 15 , wherein forming the channel layer film comprises fonning the microcrystalline thin film up to 1 nm away into the channel layer film from the interface with said insulation layer.

17. A method of forming a microcrystalline thin film, comprising:

supplying, during a source supplying process, SiH 4 and H 2 to a chamber in which a substrate is located, wherein the SiH 4 is supplied at a first rate and the H 2 is supplied at a second rate, the first and second rates defining a flow rate ratio to prevent formation of a layer of an amorphous film during the source supplying process; supplying, during a second process, H 2 but not SiH 4 to the chamber; and

depositing the microcrystalline thin film on the substrate, during the second process.

18. The method of claim 17 , further comprising:

applying an electric field in the chamber during the source supplying process to break down SiH 4 to SiH 2 molecules,

wherein a majority of the SiH 2 molecules is adsorbed on the substrate during the second process to deposit the microcrystalline thin film on the substrate.

19. A method of forming a microcrystalline thin film, comprising:

supplying, during a first process SiH 4 and H 2 to a chamber in which a substrate is located; supplying, during a second process, H 2 but not SiH 4 to the chamber; and

depositing the microcrystalline thin film on the substrate during the second process;

wherein supplying SiH 4 and H 2 comprises supplying SiH 4 at a first rate and H 2 at a second rate, the first rate and second rate defining a flow race ratio that prevents a thin film formed on the substrate from becoming amorphous.