US-12624451-B2 - Atomic layer deposition apparatus

US12624451B2US 12624451 B2US12624451 B2US 12624451B2US-12624451-B2

Abstract

An atomic layer deposition apparatus including an atomic layer deposition reactor and a reactor door. The reactor door is arranged against the end edge of the reactor in a closed position of the reactor. The apparatus having a cooling arrangement for cooling the reactor door having a shell structure surrounding the reactor from the outside of the reactor such that a cooling channel is formed between the shell structure and the at least one side wall of the reactor; a heat exchanger element arranged in the cooling channel in an area of the end edge; and a ventilation discharge connection in connection with the cooling channel provided at a distance from the edge end.

Inventors

Hulda AMINOFF
Pekka Soininen
Pekka J. Soininen
Ville MIIKKULAINEN

Assignees

BENEQ OY

Dates

Publication Date: 20260512
Application Date: 20200626
Priority Date: 20190628

Claims (16)

1 . An atomic layer deposition apparatus for processing substrates, the apparatus comprising: a reactor configured for atomic layer deposition, the reactor defining an opening to a deposition space within the reactor, the reactor comprising at least one side wall, an end edge, and a flange structure protruding from the at least one side wall of the reactor away from the deposition space, the flange structure being provided at the end edge of the reactor; and a reactor door configured to open and close the opening of the reactor, the reactor door being arranged against the flange structure in a closed position of the reactor, the reactor door including at least one radiation shield plate disposed on an inner side of the reactor door facing toward the deposition space for limiting an amount of excess heat that enters the reactor door from within the reactor, the apparatus further comprises a cooling arrangement for cooling the reactor door, the cooling arrangement comprising: a shell structure surrounding an exterior of the reactor such that a cooling channel is formed between the shell structure and the at least one side wall of the reactor; a heat exchanger element arranged in the cooling channel adjacent the end edge, the heat exchanger element having at least one air intake that provides fluid communication between an exterior of the apparatus and the cooling channel, a portion of the heat exchanger element being in contact with the flange structure to form a heat transfer connection with the flange structure for cooling the reactor door arranged against the flange structure; a ventilation discharge connection fluidly connected to the cooling channel, the ventilation discharge connection being provided at a distance from the end edge of the reactor for discharging gas entering through the at least one air intake of the heat exchanger element; and a collar arranged around the reactor adjacent the end edge, the collar comprising: a wall portion protruding away from the shell structure in a transverse direction with respect to the at least one side wall of the reactor; and a collar portion extending from the wall portion toward the end edge of the reactor, the collar portion being arranged to form together with the end edge of the reactor an opening to the cooling channel; wherein the cooling channel extends from the opening along the collar portion toward the wall portion of the collar, continues along the wall portion toward the at least one side wall of the reactor, and further extends between the shell structure and the at least one side wall of the reactor to the ventilation discharge connection.
2 . The apparatus according to claim 1 , wherein the heat exchanger element forms a heat transfer connection with the side wall of the reactor to transfer heat from the side wall of the reactor to the end edge and thereby to the reactor door.
3 . The apparatus according to claim 1 , wherein the heat exchanger element is arranged in the cooling channel at a distance of up to five centimetres from the end edge of the reactor.
4 . The apparatus according to claim 1 , wherein the heat exchanger element is made of material having a thermal conductivity of more than 50 W·m −1 ·K −1 preferably more than 100 W·m −1 ·K −1 .
5 . The apparatus according to claim 1 , wherein the cooling channel extends between the ventilation discharge connection and the end edge of the reactor.
6 . The apparatus according to claim 1 , wherein the collar guides the cooling channel from the end edge toward the side wall of the reactor such that the cooling channel extends from the opening along the collar portion toward the wall portion of the collar, continues along the wall portion toward the at least one side wall of the reactor, and further extends between the shell structure and the at least one side wall of the reactor to the ventilation discharge connection.
7 . The apparatus according to claim 1 , wherein the heat exchanger element and the wall portion of the collar together define a portion of the cooling channel extending transversely with respect to the side wall of the reactor.
8 . The apparatus according to claim 1 , wherein the shell structure including the collar portion extends along the length of the side wall of the reactor and forms a hood around the reactor door.
9 . The apparatus according to claim 1 , wherein the reactor door comprises a door structure and a perforated plate arranged at a distance from the door structure such that a space is arranged between the door structure and the perforated plate.
10 . The apparatus according to claim 9 , wherein the perforated plate comprises inlet perforations at a lower part of the perforated plate formed to provide an air passage from an exterior side of the perforated plate to the space between the door structure and the perforated plate.
11 . The apparatus according to claim 1 , wherein the heat exchanger element is arranged between the at least one side wall of the reactor and the shell structure such that the heat exchanger element extends around the reactor and from the at least one side wall to the shell structure.
12 . The apparatus according to claim 1 , wherein the cooling channel extends around the reactor such that the opening of the cooling channel is formed between the shell structure and the end edge of the reactor and extends around the end edge of the reactor.
13 . The apparatus according to claim 9 , wherein the perforated plate comprises inlet perforations at a lower part of the perforated plate formed to provide an air passage from an exterior side of the perforated plate to the space between the door structure and the perforated plate and outlet perforations at an upper part of the perforated plate formed to provide an air passage from the space between the door structure and the perforated plate to the exterior side of the perforated plate for air to be guided to the collar.
14 . The apparatus according to claim 1 , wherein the at least one radiation shield plate is configured to cool the reactor door.
15 . The apparatus according to claim 1 , wherein the at least one radiation shield plate on the reactor door helps prevent radiation heat from entering the reactor door from within the reactor.
16 . The apparatus according to claim 1 , wherein the at least one radiation shield plate is attached to the inner side of the reactor door for preventing excess heat from entering the reactor door from within the reactor.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a national phase entry under 35 U.S.C. 371 of PCT International Application No. PCT/FI2020/050463 filed Jun. 26, 2020, which claims priority to Finnish Patent Application No. 20195588, filed Jun. 28, 2019, the disclosure of each of these applications is expressly incorporated herein by reference in their entirety. FIELD OF THE INVENTION The present invention relates to an atomic layer deposition apparatus. BACKGROUND OF THE INVENTION Atomic layer deposition apparatus conventionally comprises an atomic layer deposition (ALD) reactor and precursor sources for supplying precursors to the ALD reactor. The ALD reactor may have operating temperature up to 600° C. or even more. In addition, the process typically uses about 1 mbar absolute pressure, so the reaction space must be within the pressure-resistant structures. High temperatures increase the temperature of the apparatus and parts thereof causing safety issues for users and also thermal stress issues for the apparatus itself. Therefore, the reaction chambers are most commonly located within a solid pressure vessel. The reaction chamber can be heated by directly attached resistors, internal chamber heaters, or by eternally heating the shell of the pressure vessel. However there is a problem with a large heated mass that slows down heating and cooling between process operations. In addition, the heat load that is escaping to a room in which the apparatus is positioned, is great especially if no insulators are used. Insulators, on the other hand, often contain dusty materials, with the risk of dust forming in the clean room. The externally heated reactors are often tubular, making them easily lengthy because of the temperature gradient control and keeping the door cool enough which causes problems in the size of the apparatus and its operation. When using internal heaters heat the pressure vessel must be cooled and in prior art the pressure vessel is cooled by water cooling. However there are many problems related to water cooling, especially the risk relating to leaking of water in the cooling water system which leads to water damage. Further running water into the drain is expensive and water circuits may have problems with algae growth and corrosion. BRIEF DESCRIPTION OF THE INVENTION An object of the present invention is to provide an atomic layer deposition apparatus which enables removing water cooling without increasing the size of the reactor and without having to use external insulators and further keeping the reactor door cool for safety reasons and without limiting the operating temperatures. The invention is based on the idea of providing an atomic layer deposition apparatus for processing substrates according to principles of atomic layer deposition which the apparatus comprising an atomic layer deposition reactor, a reactor door and a cooling arrangement for cooling the reactor door. The cooling arrangement uses surrounding room air for cooling. The reactor has an opening to a deposition space inside the reactor and at least one side wall and an end edge. The reactor in this application is commonly used for a vacuum chamber and a deposition space provided within the vacuum chamber. The deposition space is preferably arranged within a reaction chamber provided within the vacuum chamber. The reactor door is provided in connection with the opening for opening and closing the reactor and the reactor door is arranged against the end edge of the reactor in a closed position of the reactor. The reactor may be provided as a chamber in which one end of the chamber comprises an opening to the deposition space. The opening may extend over the entire area of the end of the chamber or alternatively the opening may form only part of the end of the chamber. In a preferred embodiment of the invention the reactor is arranged as a cylindrical chamber having only one side wall surrounding the chamber and two end walls opposite to each other. Preferably, the reactor is lying on its side wall so that the end walls are vertical or substantially vertical. In a preferred embodiment of the invention the reactor is provided such that the reactor is at the height of the user's waistline, whereby the space under the reactor may be provided with equipment or other process-related means. One or more separate reaction chambers can be arranged in the deposition space. In the apparatus according to the invention objects subjected to atomic layer deposition are arranged inside the reaction chamber(s). Separate vapor or precursor channels can be arranged to the reaction chamber to facilitate ALD deposition. Vacuum environment needed by the ALD process is provided by the deposition space. The cooling arrangement comprises a shell structure, a heat exchanger element and a ventilation discharge connection forming the cooling arrangement. The shell structure is arranged to surround the reactor from the outside of the reactor