CN213124388U - Equipment for controlling wafer curvature - Google Patents
Equipment for controlling wafer curvature Download PDFInfo
- Publication number
- CN213124388U CN213124388U CN202022129472.0U CN202022129472U CN213124388U CN 213124388 U CN213124388 U CN 213124388U CN 202022129472 U CN202022129472 U CN 202022129472U CN 213124388 U CN213124388 U CN 213124388U
- Authority
- CN
- China
- Prior art keywords
- wafer
- reaction
- gas
- control
- gas supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Chemical Vapour Deposition (AREA)
Abstract
The embodiment of the utility model provides a pair of control wafer crookedness's equipment, include: the wafer processing device comprises at least two reaction cavities, wherein a bearing device is arranged in each reaction cavity and used for bearing a wafer; the gas supply device is used for supplying reaction gas to each reaction cavity; and a control device is arranged between each reaction cavity and the gas supply device, and each control device is used for controlling the gas supply device to supply reaction gas to the corresponding reaction cavity so as to control the curvature of the wafer. Therefore, each reaction cavity is provided with the only corresponding control device, and each control device can independently control the gas supply device to supply reaction gas to the corresponding reaction cavity, so that the waste of productivity is avoided, the thickness of a film formed on a wafer in the reaction cavity can be accurately controlled, the curvature of the wafer is further accurately controlled, and the curvature difference of the whole batch of wafers is reduced.
Description
Technical Field
The utility model relates to a semiconductor device, in particular to equipment of control wafer crookedness.
Background
In the chemical vapor deposition process, the excessively large curvature (bow) of the wafer can cause the capacitive reactance impedance of plasma in the deposition process to be abnormal, so that arc discharge (arc) is easy to occur, and the maintenance of machine hardware and the improvement of the product yield are seriously influenced.
In the existing mass production process, the method for adjusting the wafer curvature mainly comprises group dep (group dep), wherein wafers with different curvature values are grouped, and then enter a machine table by taking the group as a unit for carrying out deposition together.
However, the grouping method is usually to divide wafers of each 6 μm into a batch, then to divide the wafers of the same batch into a plurality of groups for deposition, and to place each wafer in a separate reaction chamber, and the number of each group of wafers may be less than the number of the reaction chambers, and not necessarily to place each reaction chamber with wafers, so that some reaction chambers are left empty, which causes a loss of production energy, and meanwhile, because the curvature values of each wafer are different, the curvature value of each wafer cannot be accurately adjusted by the same deposition method, which results in a large difference in curvature of the whole batch of wafers.
SUMMERY OF THE UTILITY MODEL
In view of this, the utility model aims at providing a control equipment of wafer crookedness, the crookedness value of accurate adjustment wafer avoids the waste of productivity simultaneously.
In order to achieve the above purpose, the utility model has the following technical proposal:
an apparatus for controlling wafer bow, comprising:
the wafer processing device comprises at least two reaction cavities, wherein a bearing device is arranged in each reaction cavity and used for bearing a wafer;
the gas supply device is used for supplying reaction gas to each reaction cavity;
every the reaction cavity with all be provided with controlling means between the gas supply installation, every controlling means is used for controlling respectively the gas supply installation is to corresponding supply with reaction gas in the reaction cavity, in order to control the crookedness of wafer.
Optionally, the control device is specifically configured to control a flow rate and/or time of the gas supply device supplying the reaction gas into the corresponding reaction cavity.
Optionally, the number of the reaction cavities is four, and the number of the control devices is four.
Optionally, the control device is specifically configured to control the gas supply device to supply reaction gas to the corresponding reaction chamber, so as to control deposition of a silicon nitride film with a preset thickness on one side of the wafer protrusion.
Optionally, the control device is specifically configured to control the gas supply device to supply reaction gas to the corresponding reaction chamber, so as to control deposition of a silicon oxide film with a preset thickness on one side of the wafer recess.
Optionally, the preset thickness is determined according to a pre-bending value of the wafer.
Optionally, the device is used for controlling the curvature of the wafer on which the 3D-NAND memory is located.
Optionally, the control device is a flow valve installed on a gas supply pipeline of the gas supply device.
Optionally, a heating device is disposed in the supporting device, and the heating device is used for heating the wafer.
Optionally, each control device is connected to the central processing unit, the central processing unit obtains whether the wafer is placed in each reaction cavity and the curvature previous value of the wafer, and sends control information to the corresponding control device, so that each control device controls the gas supply device to supply the reaction gas to the corresponding reaction cavity.
The equipment for controlling the wafer curvature provided by the embodiment of the application comprises: the wafer processing device comprises at least two reaction cavities, wherein a bearing device is arranged in each reaction cavity and used for bearing a wafer; the gas supply device is used for supplying reaction gas to each reaction cavity; and a control device is arranged between each reaction cavity and the gas supply device, and each control device is used for controlling the gas supply device to supply reaction gas to the corresponding reaction cavity so as to control the curvature of the wafer. Therefore, each reaction cavity is provided with the only corresponding control device, and each control device can independently control the gas supply device to supply reaction gas to the corresponding reaction cavity, so that the waste of productivity is avoided, the thickness of a film formed on a wafer in the reaction cavity can be accurately controlled, the curvature of the wafer is further accurately controlled, and the curvature difference of the whole batch of wafers is reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 shows a schematic structural diagram of an apparatus for controlling wafer bow according to an embodiment of the present invention.
Detailed Description
In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be embodied in other specific forms other than those described herein, and it will be apparent to those skilled in the art that the present invention may be practiced without departing from the spirit and scope of the invention.
As described in the background art, in the conventional mass production process, the method for adjusting wafer bow mainly includes group dep, which first groups wafers with different bow values, and then enters the machine station by group for deposition together. However, the grouping method is usually to divide wafers of each 6 μm into a batch, then to divide the wafers of the same batch into a plurality of groups for deposition, and to place each wafer in a separate reaction chamber, and the number of each group of wafers may be less than the number of the reaction chambers, and to place a wafer in each reaction chamber, which results in some reaction chambers being vacant, resulting in a loss of production energy, and meanwhile, because the curvature values of each wafer are different, the curvature values of each wafer cannot be accurately adjusted by the same deposition method, resulting in a large difference in curvature of the whole batch of wafers.
To this end, an embodiment of the present application provides an apparatus for controlling wafer bow, which is shown in fig. 1 and includes:
at least two reaction cavities 101, wherein a bearing device 102 is arranged in each reaction cavity 101, and the bearing device 102 is used for bearing a wafer 140;
a gas supply device 110, wherein the gas supply device 110 is used for supplying reaction gas into each reaction cavity 101;
a control device 120 is disposed between each reaction chamber 101 and the gas supply device 110, and each control device 120 is used for controlling the gas supply device 110 to supply the reaction gas to the corresponding reaction chamber 101 so as to control the curvature of the wafer 140.
In the embodiment of the present disclosure, the reaction cavity 101 is a reaction chamber required for forming a film on a wafer or etching the wafer, the reaction cavity 101 is located in a machine, each machine has a reaction cavity, and the machine may be a chemical vapor deposition machine, such as a Metal Organic Chemical Vapor Deposition (MOCVD) machine, a Plasma Enhanced Chemical Vapor Deposition (PECVD) machine.
The upper surface of each reaction chamber 101 is provided with a gas inlet so that the reaction gas can enter the reaction chamber 101. Each reaction chamber 101 has a carrier 102, the carrier 102 is used for carrying a wafer 140, for example, one carrier 102 may be used for carrying a wafer with a certain curvature. The carrier 102 has opposite upper and lower surfaces, and in particular, the upper surface of the carrier 102 is used for carrying the wafer 140. The carrying device 102 may further include a heating device, and the heating device is configured to heat the wafer 140 on the carrying device 102, so that the wafer 140 is uniformly heated, which is beneficial to forming a thin film with uniform thickness on the wafer 140.
The wafer 140 has a front surface and a back surface, a semiconductor device, such as a 3D-NAND memory device, may be formed on the front surface, the wafer 140 is placed on the carrier 102 in the reaction chamber 101, generally, the front surface of the wafer 140 is close to the upper surface of the carrier 102, so that the back surface of the wafer 140 contacts the reaction gas in the reaction chamber 101, and a film may be deposited on the back surface of the wafer 140, and the curvature of the wafer 140 may be adjusted by adjusting the thickness of the film deposited on the back surface of the wafer 140. Depositing a film on the back side of the wafer 140 can also avoid the influence on the device structure during the film deposition process.
For example, when the warpage of the edge of the wafer 140 is greater than the warpage of the center of the wafer 140, a silicon nitride film is deposited on the back surface of the wafer 140, which is to be understood as a silicon nitride film deposited on the convex side of the wafer 140. Due to the high tensile stress of the silicon nitride film, the curvature of the convex side of the wafer 140 is reduced, so that the forward curvature value of the wafer 140 is reduced. When the warpage of the edge of the wafer 140 is smaller than the center of the wafer 140, a silicon oxide film is deposited on the back side of the wafer 140, i.e., on the recessed side of the wafer 140. Due to the high-pressure stress of the silicon oxide film, the bending degree of the concave side of the wafer 140 can be reduced, and thus the negative bending degree value of the wafer 140 is reduced. In the embodiment of the present invention, the gas supply device 110 is used for supplying a reaction gas into each reaction chamber 101, and the reaction gas reacts in the reaction chamber 101 to form a thin film on the wafer 140. The reaction gas may be, for example, silane and nitrogen, and the silane and nitrogen are introduced into the reaction chamber 101 to deposit a silicon nitride film on the wafer 140. The reactant gas may also be silane and oxygen to deposit a silicon oxide film on the wafer 140. Before the gas supply device 110 supplies the reaction gas into each reaction chamber 101, an inert gas may be supplied into each reaction chamber 101 to prevent the reaction gas from being contaminated by other gases or impurity ions in the reaction chamber 101.
Generally, the gas supply device 110 supplies the reaction gases into the plurality of reaction chambers 101 at the same time, but the applicant finds that, instead of placing a wafer in each reaction chamber 101 of the machine, the gas supply device 110 supplies the gases into the plurality of reaction chambers 101 at the same time, that is, the reaction gases are simultaneously introduced into the reaction chambers 101 where wafers are placed and the reaction chambers 101 where wafers are not placed, thereby wasting productivity. The curvature values of the wafers 140 in the reaction chambers 101 are not necessarily completely the same, and the reaction gas is introduced into the reaction chambers 101, so that the thicknesses of the films deposited on the wafers in the reaction chambers 101 are the same, and the curvature of each wafer cannot be accurately adjusted.
Therefore, the applicant provides a control device 120 between each reaction chamber 101 and the gas supply device 110, and referring to fig. 1, each reaction chamber has a control device 120 uniquely corresponding thereto, each control device 120 can individually control the reaction gas supplied from the gas supply device 110 to the corresponding reaction chamber 101, thereby avoiding waste of productivity, and can precisely control the thickness of the thin film formed on the wafer 140 in the reaction chamber 101, and further precisely control the curvature of the wafer 140.
In this embodiment, the control device 120 is used to control the flow rate and/or time of the gas supply device 110 supplying the reaction gas into the corresponding reaction chamber 101. In a specific embodiment, the film thickness required for adjusting the wafer curvature value of the wafer 140 may be determined according to the corresponding relationship between the wafer curvature value and the film thickness and the wafer curvature value of the wafer 140 in the reaction chamber 101. Then, the relationship between the flow rate of the reaction gas and the film thickness in a certain time can be obtained, the flow rate of the reaction gas to be supplied to the reaction chamber 101 is determined according to the relationship, and the flow rate of the reaction gas to be supplied to the reaction chamber 101 is controlled by controlling the gas supply device 110. The relationship between the time of the reaction gas and the film thickness at a constant gas flow rate may be obtained, the time required to supply the reaction gas into the reaction chamber 101 may be determined based on the relationship, and the time required to supply the reaction gas into the reaction chamber 101 may be controlled by controlling the gas supply device 110. In a specific application, the control device 120 may be a flow valve on the gas supply pipeline 112 of the gas supply device 110, each reaction chamber 101 has a corresponding gas supply pipeline 112, and the flow rate and/or time of supplying gas to the corresponding reaction chamber 101 may be controlled according to the flow valve.
In this embodiment, the number of the reaction chambers 101 is four, and the number of the control devices 120 is four. For convenience of description, the four reaction chambers are divided into a first reaction chamber, a second reaction chamber, a third reaction chamber and a fourth reaction chamber, a control device corresponding to the first reaction chamber is called a first control device, a control device corresponding to the second reaction chamber is called a second control device, a control device corresponding to the third reaction chamber is called a third device, and a control device corresponding to the fourth reaction chamber is called a fourth control device. The first control device controls the gas supply device to supply gas into the first reaction cavity, the second control device controls the gas supply device to supply gas into the second reaction cavity, the third control device controls the gas supply device to supply gas into the third reaction cavity, and the fourth control device controls the gas supply device to supply gas into the fourth reaction cavity.
Specifically, the first control device controls the flow and/or time of the reaction gas supplied by the gas supply device to the first reaction chamber according to the curvature previous value of the wafer in the first reaction chamber; the second control device controls the flow and/or time of the reaction gas supplied by the gas supply device to the second reaction cavity according to the curvature previous value of the wafer in the second reaction cavity; the third control device controls the flow and/or time of the reaction gas supplied by the gas supply device to the third reaction chamber according to the bending degree front value of the wafer in the third reaction chamber; and the fourth device controls the flow and/or time of the reaction gas supplied into the fourth reaction chamber by the gas supply device according to the curvature previous value of the wafer in the reaction chamber of the fourth machine.
When the pre-curvature values of the wafers in the first reaction chamber, the second reaction chamber, the third reaction chamber and the fourth reaction chamber are different, the flow rate of the reaction gas supplied into the first reaction chamber, the flow rate of the reaction gas supplied into the second reaction chamber, the flow rate of the reaction gas supplied into the third reaction chamber and the flow rate of the reaction gas supplied into the fourth reaction chamber are different at the same time. Specifically, the larger the pre-bending value of the wafer in the reaction chamber, the larger the flow rate of the reaction gas supplied thereto.
Alternatively, the time for supplying the reaction gas into the first reaction chamber, the time for supplying the reaction gas into the second reaction chamber, the time for supplying the reaction gas into the third reaction chamber, and the time for supplying the reaction gas into the fourth reaction chamber may be different from each other at the same gas flow rate. Specifically, the larger the pre-bending value of the wafer in the reaction chamber, the longer the reaction gas is supplied thereto.
Alternatively, the time for supplying the reaction gas into the first reaction chamber, the time for supplying the reaction gas into the second reaction chamber, the time for supplying the reaction gas into the third reaction chamber, and the time for supplying the reaction gas into the fourth reaction chamber are different from each other, and the flow rate of the reaction gas supplied into the first reaction chamber, the flow rate of the reaction gas supplied into the second reaction chamber, the flow rate of the reaction gas supplied into the third reaction chamber, and the flow rate of the reaction gas supplied into the fourth reaction chamber are different from each other. Specifically, the larger the pre-bending value of the wafer in the reaction chamber, the larger the flow rate of the reaction gas supplied thereto, and the longer the time for supplying the reaction gas thereto. Therefore, films with different thicknesses can be deposited on the wafers with different values before the bending so as to control the bending of the wafers.
In a specific application, when the warpage of the edge of the wafer 140 in the reaction chamber 101 is greater than the warpage of the center of the wafer 140, the control device 120 controls the gas supply device 110 to supply the reaction gas to the corresponding reaction chamber 101 in the machine 100, so as to control the deposition of the silicon nitride film with a predetermined thickness on the convex side of the wafer 140. When the warpage of the edge of the wafer 140 in the reaction chamber 101 is smaller than the warpage of the center of the wafer 140, the control device 120 controls the gas supply device 110 to supply the reaction gas to the corresponding reaction chamber 101 in the machine 100, so as to control the deposition of the silicon oxide film with a predetermined thickness on the recessed side of the wafer 140. The predetermined thickness is determined according to the pre-curvature value of the wafer 140, so that the curvature of the wafer can be accurately controlled.
In this embodiment, each control device 120 is connected to a central processing unit, the central processing unit can obtain information such as whether a wafer is placed in each reaction cavity and a curvature pre-value of the wafer, and then the central processing unit sends the obtained information to a control device corresponding to the reaction cavity, each control device respectively controls the gas supply device to supply the reaction gas to the corresponding reaction cavity according to the received information sent by the central processing unit, for example, if the wafer is not placed in the first reaction cavity, the control device controls the gas supply device to close a channel for supplying the reaction gas to the corresponding first reaction cavity.
As described in detail above for the apparatus for controlling wafer curvature provided by the embodiment of the present application, a control device is disposed between each reaction chamber and the gas supply device, and each control device is used to control the gas supply device to supply reaction gas to the corresponding reaction chamber, so as to control the wafer curvature. Therefore, each reaction cavity is provided with the only corresponding control device, and each control device can independently control the gas supply device to supply reaction gas to the corresponding reaction cavity, so that the waste of productivity is avoided, the thickness of a film formed on a wafer in the reaction cavity can be accurately controlled, the curvature of the wafer is further accurately controlled, and the curvature difference of the whole batch of wafers is reduced.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments.
The above description is only for the preferred embodiment of the present invention, and although the present invention has been disclosed in the preferred embodiments, it is not intended to limit the present invention. The invention is not limited to the embodiments described herein, but is capable of other embodiments according to the invention, and may be used in various other applications, including, but not limited to, industrial. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical substance of the present invention all fall within the protection scope of the technical solution of the present invention.
Claims (10)
1. An apparatus for controlling wafer bow, comprising:
the wafer processing device comprises at least two reaction cavities, wherein a bearing device is arranged in each reaction cavity and used for bearing a wafer;
the gas supply device is used for supplying reaction gas to each reaction cavity;
every the reaction cavity with all be provided with controlling means between the gas supply installation, every controlling means is used for controlling respectively the gas supply installation is to corresponding supply with reaction gas in the reaction cavity, in order to control the crookedness of wafer.
2. The apparatus according to claim 1, wherein the control device is specifically configured to control the flow rate and/or the time of supplying the reaction gas into the corresponding reaction chamber by the gas supply device.
3. The apparatus of claim 1 or 2, wherein the number of reaction chambers is four and the number of control devices is four.
4. The apparatus of claim 1, wherein the control device is specifically configured to control the gas supply device to supply the reaction gas into the corresponding reaction chamber, so as to control deposition of a silicon nitride film with a predetermined thickness on the convex side of the wafer.
5. The apparatus of claim 1, wherein the control device is specifically configured to control the gas supply device to supply the reaction gas to the corresponding reaction chamber, so as to control deposition of a silicon oxide film with a predetermined thickness on one side of the wafer recess.
6. An apparatus according to claim 4 or 5, wherein the predetermined thickness is determined from a pre-bow value of the wafer.
7. The apparatus of claim 1, wherein the apparatus is used for bow control of a wafer on which the 3D-NAND memory is located.
8. The apparatus of claim 1, wherein the control device is a flow valve mounted on a gas supply conduit of the gas supply.
9. The apparatus of claim 1, wherein the carrier has a heating device disposed therein for heating the wafer.
10. The apparatus according to claim 1, wherein each of the control devices is connected to a central processing unit, and the central processing unit respectively obtains whether a wafer is placed in each reaction chamber and a pre-curvature value of the wafer, and sends control information to the corresponding control device, so that each control device respectively controls the gas supply device to supply reaction gas to the corresponding reaction chamber.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022129472.0U CN213124388U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
| CN202121094104.5U CN214624989U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022129472.0U CN213124388U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121094104.5U Division CN214624989U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213124388U true CN213124388U (en) | 2021-05-04 |
Family
ID=75664755
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121094104.5U Active CN214624989U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
| CN202022129472.0U Active CN213124388U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121094104.5U Active CN214624989U (en) | 2020-09-24 | 2020-09-24 | Equipment for controlling wafer curvature |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN214624989U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113584465A (en) * | 2021-07-30 | 2021-11-02 | 长鑫存储技术有限公司 | Chemical vapor deposition apparatus |
-
2020
- 2020-09-24 CN CN202121094104.5U patent/CN214624989U/en active Active
- 2020-09-24 CN CN202022129472.0U patent/CN213124388U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113584465A (en) * | 2021-07-30 | 2021-11-02 | 长鑫存储技术有限公司 | Chemical vapor deposition apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| CN214624989U (en) | 2021-11-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102503328B1 (en) | Adjustable side gas plenum for edge etch rate control in a downstream reactor | |
| KR102598660B1 (en) | Systems and methods for reducing backside deposition and mitigating thickness changes at substrate edges | |
| KR100372956B1 (en) | Film forming device | |
| US20150004798A1 (en) | Chemical deposition chamber having gas seal | |
| JP2005123532A (en) | Deposition system and deposition method | |
| KR20170107935A (en) | Symmetric plasma source to generate pie shaped treatment | |
| TWI793303B (en) | Continuous apparatus and method for coating substrates | |
| CN213124388U (en) | Equipment for controlling wafer curvature | |
| KR20100126257A (en) | Method of depositing metallic film and memory medium | |
| CN102272897A (en) | Plasma processing apparatus and plasma cvd film-forming method | |
| CN212199412U (en) | Reaction device for plasma atomic layer deposition | |
| JPH0786174A (en) | Film deposition system | |
| KR101321677B1 (en) | Substrate processing apparatus | |
| US20100277050A1 (en) | Plasma processing apparatus | |
| US8395250B2 (en) | Plasma processing apparatus with an exhaust port above the substrate | |
| US9297075B2 (en) | Plasma deposition apparatus and plasma deposition method | |
| US20220136104A1 (en) | Multi-station semiconductor processing with independently adjustable pedestals | |
| JP2023509475A (en) | A showerhead with a faceplate having an internal contour | |
| CN114369813A (en) | Diffusion furnace | |
| JP2020510307A (en) | Diffuser design for fluidity CVD | |
| KR102122100B1 (en) | Method and apparatus for processing a semiconductor workpiece | |
| CN220012796U (en) | Film feeding chamber device of film plating equipment | |
| CN113078081B (en) | Furnace tube machine platform | |
| JPS58132932A (en) | Plasma processing device | |
| US20230143108A1 (en) | Furnace and method for forming film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |