CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2018-0119746, filed on Oct. 8, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

1. Field

One or more embodiments relate to a substrate support unit, a thin film deposition apparatus including the substrate support unit, and a substrate processing apparatus including the substrate support unit, and more particularly, to a substrate support unit used to deposit a thin film on a pattern structure using plasma enhanced atomic layer deposition (PEALD) and a thin film deposition apparatus.

2. Description of the Related Art

Plasma enhanced atomic layer deposition (PEALD) has the advantage of depositing a thin film at low temperature over the existing thermal atomic layer deposition where a film is deposited at a high temperature. This advantage may be achieved by sequentially introducing a reactive gas or a source gas intermittently, and activating and ionizing at least one of the gases by plasma.

In a PEALD process, RF power is typically coupled to an upper electrode, e.g., a showerhead, located at the top of a reactor to generate plasma in a reaction space. However, when a thin film is deposited on a pattern structure (e.g., a pattern structure having a trench) on a substrate by using plasma, characteristics of a thin film deposited on the top of the pattern directly exposed to plasma and a thin film deposited on a trench wall and the bottom of the trench that are less exposed to plasma are not uniform.

SUMMARY

One or more embodiments include a substrate support unit used to form a uniform thin film on a pattern structure having a trench or a recess and a thin film deposition apparatus.

One or more embodiments include a method of depositing a thin film of uniform film quality on a side wall portion and a bottom portion of a trench in a pattern structure and improving conformality of a wet etch rate (WER) during a subsequent wet etching process.

Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

According to one or more embodiments, a substrate support unit in which a substrate is seated on an upper portion includes a heater; an RF electrode; a first rod connected to the heater; a second rod connected to the RF electrode; and an RF shield spaced apart from the second rod, disposed to surround the second rod, and extending in an extension direction of the second rod.

According to an example of the substrate support unit, the RF electrode may be disposed on the heater.

According to another example of the substrate support unit, the RF electrode may have a shape corresponding to a shape of the substrate.

According to another example of the substrate support unit, the substrate support unit may further include: an insulating material disposed between the heater and the RF electrode.

According to another example of the substrate support unit, the substrate support unit may further include: a first insulating member disposed between the second rod and the RF shield.

According to another example of the substrate support unit, the substrate support unit may further include: a socket configured to connect the second rod to a plasma generation unit; a ground bracket configured to connect the RF shield to ground; and a second insulating member disposed between the socket and the ground bracket.

According to another example of the substrate support unit, the substrate support unit may further include: a fixing unit configured to fix a position of the RF shield; and a body configured to surround and support the fixing unit, wherein the body is spaced apart from the RF shield and the ground bracket.

According to another example of the substrate support unit, the fixing unit may include an upper fixing unit contacting an upper portion of the RF shield and a lower fixing unit contacting a lower portion of the RF shield, wherein a part of the lower fixing unit is configured to completely surround a circumference of the RF shield, the other part of the lower fixing unit is configured to partially surround the circumference of the RF shield, and an air gap is formed in a part not surrounded by the lower fixing unit.

According to another example of the substrate support unit, the ground bracket may include a first portion extending in the same direction as the extension direction of the second rod; and a second portion extending in a direction different from the extension direction of the second rod, wherein the first portion is connected to the RF shield, and wherein the second portion is connected to the ground.

According to another example of the substrate support unit, a difference between an inner diameter of the RF shield and a diameter of the second rod may be the same as a sum of a thickness of the first portion and a thickness of a second insulating member.

According to an example of the substrate support unit, the substrate support unit may further include: a power supply unit connected to the first rod and configured to supply power to the heater. In an additional embodiment, the substrate support unit may further include: a first low-pass filter disposed between the first rod and the power supply unit. In this case, selectively, the first low-pass filter may be configured to pass a signal having a band below a frequency of RF power generated by a plasma generation unit.

According to another example of the substrate support unit, the substrate support unit may further include: a thermocouple connected to the heater; and a temperature control unit configured to receive an electrical signal from the thermocouple and control a power supply unit. In an additional embodiment, the substrate support unit may further include: a second low pass filter electrically connected to the thermocouple and configured to block a signal of a frequency band of RF power generated by a plasma generation unit among signals delivered to the temperature control unit.

According to another example of the substrate support unit, the substrate support unit may further include a plasma generation unit connected to the second rod; and a capacitive element disposed between the second rod and the plasma generation unit. In this case, selectively, the plasma generation unit may be configured to form a bias toward the substrate support unit.

According to one or more embodiments, a thin film apparatus may include the above-described substrate support unit.

According to one or more embodiments, a thin film deposition apparatus includes a substrate support unit in which a substrate is seated on an upper portion; a gas supply unit disposed on the substrate support unit; and a plasma generation unit connected to the substrate support unit.

According to one or more embodiments, a substrate processing apparatus includes a substrate support unit in which a substrate is seated on an upper portion; a gas supply unit disposed on the substrate support unit; a plasma generation unit connected to the substrate support unit; an RF rod configured to supply an RF current to the substrate support unit; and an RF shield disposed to surround the RF rod.

