US-12618146-B2 - System and method for forming large-area electronic-grade metal chalcogen thin films

Abstract

A vapor deposition system is described. The vapor deposition system includes a reaction chamber and a reactant delivery subsystem coupled with the reaction chamber. The reaction chamber is configured to retain a substrate therein. The reactant delivery subsystem includes inlets, a pre-reaction region, and outlets. The inlets receive precursors and chalcogen precursor(s). The pre-reaction region is configured to receive the precursors from a portion of the inlets and to react at least a portion of the precursors to form modified precursor(s). The modified precursor(s) are more thermally stable than metal-containing precursor(s) of the precursors used to form the modified precursor(s). The outlets are coupled with the reaction chamber and the pre-reaction region. The outlets separately provide the modified precursor(s) and the chalcogen precursor(s) to the reaction chamber. The modified precursor(s) and the chalcogen precursor(s) react and form a chalcogen film on the substrate in the reaction chamber.

Inventors

• Lain-Jong Li
• Yi Wan
• Yu-Ming Chang

Assignees

• THE UNIVERSITY OF HONG KONG

Dates

Publication Date

20260505

Application Date

20240903

Claims (18)

1. 1 . A vapor deposition system, comprising: a reaction chamber configured to retain a substrate therein; and a reactant delivery subsystem coupled with the reaction chamber and including: a plurality of inlets for receiving a plurality of precursors and at least one chalcogen precursor; a pre-reaction region configured to receive the plurality of precursors from a portion of the plurality of inlets and react at least a portion of the plurality of precursors to form a modified precursor, the modified precursor being more thermally stable than a metal-containing precursor of the at least the portion of the plurality of precursors; and a plurality of outlets coupled with the reaction chamber and the pre-reaction region, the plurality of outlets being configured to provide the modified precursor from the pre-reaction region to the reaction chamber and to separately provide the at least one chalcogen precursor to the reaction chamber that is configured to retain the substrate; wherein the substrate has a surface having a substrate area, the plurality of outlets for the at least one chalcogen precursor and for the modified precursor are distributed and interspersed over an area, at least a portion of the area being aligned with at least a portion of the substrate area; and wherein the modified precursor and the at least one chalcogen precursor react and form a chalcogen film on the substrate in the reaction chamber.
2. 2 . The vapor deposition system of claim 1 , wherein the reactant delivery subsystem includes: a heated pre-reaction chamber including the pre-reaction region therein, the at least the portion of the plurality of precursors reacting to form the modified precursor in the absence of the at least one chalcogen precursor within the heated pre-reaction chamber; and a distribution unit coupled with the heated pre-reaction chamber by a flow channel, the distribution unit including the plurality of outlets and being coupled with at least one inlet of the plurality of inlets for the at least one chalcogen precursor.
3. 3 . The vapor deposition system of claim 1 , wherein the pre-reaction region is adjacent to the plurality of outlets and the plurality of precursors react to form the modified precursor in the absence of the at least one chalcogen precursor within the pre-reaction region.
4. 4 . The vapor deposition system of claim 1 , wherein the pre-reaction region includes a heater.
5. 5 . The vapor deposition system of claim 4 , wherein a temperature of the pre-reaction region is less than a reaction chamber temperature of the reaction chamber.
6. 6 . The vapor deposition system of claim 4 , wherein the reactant delivery subsystem further includes: a cooling region coupled with the portion of the plurality of inlets and the pre-reaction region, the cooling region configured to maintain a cooling region temperature less than a disassociation temperature of the metal-containing precursor.
7. 7 . The vapor deposition system of claim 1 , wherein the plurality of precursors includes a modifier for the metal-containing precursor, the modifier reacting with the metal-containing precursor in the pre-reaction region to form the modified precursor.
8. 8 . The vapor deposition system of claim 1 , wherein the modified precursor has a higher disassociation temperature than the metal-containing precursor.
9. 9 . The vapor deposition system of claim 1 , wherein the plurality of precursors includes a dopant precursor, the chalcogen film including a dopant in the dopant precursor.
10. 10 . The vapor deposition system of claim 1 , wherein a first portion of the plurality of outlets is coupled with the pre-reaction region and provides the modified precursor to the reaction chamber; and wherein a second portion of the plurality of outlets provides the at least one chalcogen precursor to the reaction chamber separately from the modified precursor.
11. 11 . The vapor deposition system of claim 1 , wherein the reactant delivery subsystem further includes: a gas distribution system coupled with the plurality of outlets such that at least a portion of the plurality of outlets have a separately controllable flow rate.
12. 12 . The vapor deposition system of claim 1 , wherein the area is at least ½ of the substrate area.
13. 13 . The vapor deposition system of claim 1 , wherein the metal-containing precursor includes at least one of W or Mo element, the plurality of precursors includes at least one of water, Fe dopant, or V dopant, and the at least one chalcogen precursor includes at least one of S, Te, or Se element.
14. 14 . The vapor deposition system of claim 1 , wherein the pre-reaction region is included in a pre-reaction chamber and wherein the reactant delivery subsystem further includes: a mixing chamber coupled between the pre-reaction region and the plurality of outlets, the mixing chamber being configured to receive the modified precursor from the pre-reaction region and provide the modified precursor to the plurality of outlets.
15. 15 . The vapor deposition system of claim 1 , wherein the reaction chamber is configured to allow mixing of the modified precursor and the at least one chalcogen precursor in a portion of the reaction chamber between the plurality of outlets and the substrate area.
16. 16 . A method, comprising: reacting at least a portion of a plurality of precursors in a pre-reaction region to form a modified precursor, the modified precursor being more thermally stable than a metal-containing precursor of the at least the portion of the plurality of precursors; and separately providing the modified precursor from the pre-reaction region and at least one chalcogen precursor to a reaction chamber that is configured to retain a substrate; wherein the substrate has a surface having a substrate area, the separately providing including separately providing the at least one chalcogen precursor and the modified precursor from a plurality of outlets distributed and interspersed over an area, at least a portion of the area being aligned with at least a portion of the substrate area; and wherein the modified precursor and the at least one chalcogen precursor react and form a chalcogen film on the substrate in the reaction chamber.
17. 17 . The method of claim 16 , further comprising: delivering the plurality of precursors to the pre-reaction region, the plurality of precursors including a dopant precursor; and wherein the dopant in the dopant precursor is incorporated in the chalcogen film, forming a doped chalcogen film on the substrate in the reaction chamber.
18. 18 . The method of claim 16 , wherein the plurality of precursors further includes modifier for the metal-containing precursor.

Description

CROSS REFERENCE TO OTHER APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63/582,708 entitled VAPOR DEPOSITION AND DOPING METHOD TO FORM LARGE-AREA ELECTRONIC-GRADE METAL CHALCOGEN ULTRATHIN FILMS filed Sep. 14, 2023 which is incorporated herein by reference for all purposes. BACKGROUND OF THE INVENTION Two-dimensional (2D) transition metal chalcogenide (TMC) materials may include binary, ternary, quaternary, and multinary oxides, sulfides, selenides, and tellurides. TMCs have applications in a variety of fields. For example, 2D TMCs, such as MoS2, WSe2, WS2, MoTe2, MoSe2, SnS2, and SnS, may be semiconductors. Such films, as well as other TMC materials (e.g. TMCs in the form of metals such as WTe2, TiSe2), may be used in electronic applications. Although TMCs are of interest, growing TMC films using conventional vapor deposition techniques (e.g. chemical vapor deposition (CVD) and/or atomic layer deposition (ALD)) suffers from a variety of drawbacks. Conventional vapor deposition techniques may require precise temperature control within a narrow range. This makes processing more difficult and costly. Such techniques may also suffer from poor process efficiency because many volatile metal-containing precursors have a low decomposition temperature. These precursors may decompose before reaching the reaction temperature for formation of the TMC. Such metal-containing precursors may also have a small diffusion length, resulting in TMC films that are grown over only a small area of the substrate (e.g. on the order of one or two square centimeters or less). Doping using conventional vapor deposition may also be problematic. Although dopants may be introduced to the reaction chamber in a gaseous phase, the resulting materials may not have the desired uniformity or concentration of dopants. Carbon residue, which originates from organic ligand(s) in the precursors, may present a serious issue in vapor deposition systems. Consequently, techniques for formation of chalcogenides, particularly 2D TMCs, are desired. BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings. FIG. 1 is a block diagram depicting an embodiment of a vapor deposition system for providing a metal chalcogenide material. FIG. 2 is a diagram depicting an embodiment of a vapor deposition system for providing a metal chalcogenide material. FIG. 3 is a diagram depicting an embodiment of a vapor deposition system for providing a metal chalcogenide material. FIGS. 4A-4D are diagrams depicting a portion of a vapor deposition system for providing a metal chalcogenide material. FIG. 5 is a diagram depicting an embodiment of a gas distribution system for a vapor deposition system usable in fabricating a metal chalcogenide material. FIGS. 6A-6D are diagrams depicting an embodiment of a vapor deposition system usable in fabricating a metal chalcogenide material. FIG. 7 is a flow chart depicting an embodiment of a method for forming a metal chalcogenide material using vapor deposition. FIG. 8 is a flow chart depicting an embodiment of a method for forming a metal chalcogenide material using vapor deposition. FIGS. 9A-9C depict an embodiment of a metal chalcogenide film fabricated using vapor deposition and film properties. DETAILED DESCRIPTION The invention can be implemented in numerous ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer readable storage medium; and/or a processor, such as a processor configured to execute instructions stored on and/or provided by a memory coupled to the processor. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. In general, the order of the steps of disclosed processes may be altered within the scope of the invention. Unless stated otherwise, a component such as a processor or a memory described as being configured to perform a task may be implemented as a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. As used herein, the term ‘processor’ refers to one or more devices, circuits, and/or processing cores configured to process data, such as computer program instructions. A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provide