Sequential chemical vapor deposition

• US 6,652,924 B2
• Filed: 05/24/2001
• Issued: 11/25/2003
• Est. Priority Date: 08/16/1996
• Status: Expired due to Term

• Current Assignee: ASM International NV
• Original Assignee: Licensee For Microelectronics ASM America Incorporated
• Inventors: Sherman, Arthur
• Primary Examiner(s): MEEKS, TIMOTHY HOWARD
• Application Number:
  US09/866,156
• Publication Number:
  US 20010028924A1
• Time in Patent Office: 915 Days
• Field of Search: 427/252, 427/255.31, 427/255.394, 427/255.7, 427/562, 427/563, 427/564, 427/576, 427/579, 117/92, 117/103, 117/104
• US Class Current: 427/576
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• CPC Class Codes: C23C 16/45529 specially adapted for making a layer stack of alternating different compositions or gradient compositions
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/4554 Plasma being used non-continuously in between ALD reactions C23C16/56 takes precedence
• CPC Class Codes: C23C 16/45542 Plasma being used non-continuously during the ALD reactions
• CPC Class Codes: C23C 16/45544 characterized by the apparatus
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: C30B 25/14 Feed and outlet means for the gases; Modifying the flow of the reactive gases

Abstract

The present invention provides for sequential chemical vapor deposition by employing a reactor operated at low pressure, a pump to remove excess reactants, and a line to introduce gas into the reactor through a valve. A first reactant forms a monolayer on the part to be coated, while the second reactant passes through a radical generator which partially decomposes or activates the second reactant into a gaseous radical before it impinges on the monolayer. This second reactant does not necessarily form a monolayer but is available to react with the monolayer. A pump removes the excess second reactant and reaction products completing the process cycle. The process cycle can be repeated to grow the desired thickness of film.

Claims

1. A process of growing a thin film by a sequential vapor deposition process, comprising the steps of:

placing a part in a chamber;

removing gases from the chamber;

exposing the part to a gaseous first reactant, including an element of the thin film to be formed, wherein the first reactant adsorbs on the part in a self-limiting manner;

removing gases from the chamber;

exposing the part, coated with the first reactant, to a gaseous second reactant of radicals, wherein the radicals convert the first reactant on the part to one or more elements, wherein a conductive or insulating thin film is formed; and

removing gases from the chamber.

2. The process of claim 1, wherein the parts to be coated are maintained at temperatures up to 500°

C. in the chamber.

3. The process of claim 1, wherein the first reactant includes a halogen atom.

4. The process of claim 1, wherein the first reactant is a metal-organic molecule including an elemental metal species.

5. The process of claim 1, wherein the radicals of the second reactant are selected from the group consisting of oxygen atoms, nitrogen atoms, hydrogen atoms, OH molecules, NH molecules or a combination thereof.

6. The process of claim 1, wherein the radicals of the second reactant are rated in a radical generator in communication with the chamber.

7. The process of claim 1, where in the radicals of the second reactant are generated by surrounding the chamber with an RF excitation coil, wherein the thin film being formed is a dielectric material.

8. The process of claim 1, wherein the first reactant is tetraethoxysilane and the second reactant is atomic oxygen which converts the first reactant to a thin film of silicon dioxide.

9. The process of claim 1, wherein the first reactant is titanium tetrachloride and the second reactant is atomic hydrogen which converts the first reactant to a thin film of titanium.

10. The process of claim 1, wherein the first reactant is a titanium organometallic compound and the second reactant is hydrogen atoms or HN molecules which convert the first reactant to a thin film of titanium nitride.

11. The process of claim 1, wherein the first reactant is an aluminum compound and the second reactant is atomic hydrogen which converts the first reactant to a thin film of aluminum.

12. The process of claim 1, wherein the first reactant is a copper compound and the second reactant is atomic hydrogen which converts the first reactant to a thin film of copper.

13. A process of growing a thin film by a vapor deposition process, comprising the steps of:

placing a part in a chamber; and

a plurality of cycles, each cycle comprising;

exposing the part to a gaseous first reactant, containing a metal element, wherein the first reactant adsorbs on the part in a self-limiting manner;

removing excess first reactant gases from the chamber;

exposing the part, coated with the first reactant, to a gaseous second reactant of radicals, wherein the radicals convert the first reactant on the part to the metal element; and

removing excess second reactant gases from the chamber.

14. The process of claim 13, wherein the first reactant is a metal selected from a group consisting of aluminum, copper, tantalum, titanium, and tungsten, and the second reactant is a radical selected from a group consisting of hydrogen, nitrogen, oxygen, or a combination thereof.

15. A process of growing a thin film by a repetitive vapor deposition process, which comprises:

placing a part in a chamber; and

a plurality of cycles, each cycle comprising;

exposing the part to a gaseous first reactant including an element selected from the group consisting of Si and Ge, wherein a portion of the first reactant adsorbs on the part in a self-limiting manner;

removing gases from the chamber;

exposing the part, coated with the portion of the first reactant, to a gaseous second reactant of radicals selected from the group consisting of O and N, wherein the radicals convert the portion of the first reactant on the part to a thin film selected from the group consisting of silicon nitride, silicon oxide, germanium nitride, germanium oxide; and

removing excess second reactant gases from the chamber.