CN104233227A - Atomic layer deposition equipment and method - Google Patents
Atomic layer deposition equipment and method Download PDFInfo
- Publication number
- CN104233227A CN104233227A CN201410487817.6A CN201410487817A CN104233227A CN 104233227 A CN104233227 A CN 104233227A CN 201410487817 A CN201410487817 A CN 201410487817A CN 104233227 A CN104233227 A CN 104233227A
- Authority
- CN
- China
- Prior art keywords
- remote plasma
- atomic layer
- layer deposition
- reaction chamber
- atomic
- 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.)
- Pending
Links
Landscapes
- Chemical Vapour Deposition (AREA)
Abstract
The invention provides atomic layer deposition equipment and a method. In the atomic layer deposition equipment, a remote plasma generator is arranged and used for generating remote plasma, a remote plasma inlet is correspondingly arranged on a cavity body of a reaction cavity, and a remote plasma pipeline is arranged and used for communicating the remote plasma generator with the remote plasma inlet and conveying the remote plasma coming out from the remote plasma generator to the remote plasma inlet. During an atomic layer deposition process, processes of atomic layer deposition and impurity removal by remote plasma are circulated, so that the surface of an atomic layer deposited each time can be cleaned, impurity defects in the atomic layer deposition process are reduced, and the cleanliness of an atomic layer film is improved; in addition, the remote plasma is utilized to avoid damage to the atomic layer and a silicon chip. The atomic layer deposition equipment can be obtained by improving the existing atomic layer deposition equipment, so as to lower the cost for replacing the equipment.
Description
Technical field
The present invention relates to technical field of semiconductors, be specifically related to a kind of atomic layer deposition apparatus and method.
Background technology
Along with chip fabrication techniques strides forward to the novel technique node that size is less, chip manufacturer needs to solve the treater energy consumption problem become increasingly conspicuous while providing more high performance chips.Compare conventional multi-crystalline silicon silicon oxynitride technique (Poly SiON), the excessive high energy consumption problem that causes of the electric leakage of the grid flow density (Jg) of transistor and depletion of polysilicon (Poly Si Depletion) problem is efficiently solved in the high-dielectric constant metal grid pole technique that 28 nm technology node are widely adopted, simultaneously in important devices parameter as threshold voltage (Vt) and equivalent oxide thickness (EOT, Equivalent Oxide Thickness) control aspect are significantly improved.In order to improve the homogeneity of high-dielectric constant metal grid pole dielectric matter film, ald (Atomic Layer Deposition) technology is widely used.Ald speed of response is very fast, and temperature of reaction does not need too high, how below 400 DEG C.
A problem of technique for atomic layer deposition is the impurity (impurity) produced in deposition process, such as, when using organic matter precursor, the organic composition impurity of carbon containing, can remain in deposited atomic layer level thin film, and stop (block) presoma (precursor) absorption on deposited atomic layer level thin film (adsorption), affect follow-up quality of forming film.
For the problems referred to above, a kind of method of improvement is: the increase rapid thermal anneal process (Rapid Thermal Anneal) in atomic layer deposition cycles process, to drive the impurity (impurity) produced in deposition process, provide clean atomic layer level thin film interface to next deposition cycle.But be limited to thermal budget (thermal budget), annealing process temperature can not be too high, have impact on Impurity removal effect.
Summary of the invention
In order to overcome above problem, the present invention aims to provide a kind of atomic layer deposition apparatus and Atomic layer deposition method, thus effectively removes the impurity of the atomic level surface deposited.
The invention provides a kind of atomic layer deposition apparatus, comprise reaction chamber, air feed port and steam line, vacuum extractor, described atomic layer deposition apparatus also comprises:
Remote plasma generator, for generation of remote plasma;
Remote plasma entrance, is arranged on the cavity of described reaction chamber, for inputting remote plasma in described reaction chamber;
Remote plasma pipeline, is connected described remote plasma generator with described remote plasma entrance, for being delivered to described remote plasma ingress by from described remote plasma generator remote plasma out.
Preferably, described atomic layer deposition apparatus also comprises: remote plasma flow direction controller, for control described remote plasma along silicon chip surface and the direction parallel with described silicon chip surface flow.
Preferably, described remote plasma flow direction controller, controls described remote plasma and flows in the horizontal direction.
Present invention also offers a kind of Atomic layer deposition method adopting above-mentioned atomic layer deposition apparatus to carry out, it comprises:
Step 01: silicon chip is placed in described reaction chamber, and utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 02: start to pass into described reactant gases, described reactant gases enters in described reaction chamber through described steam line and air feed port, at the surface deposition single or multiple lift atomic shell of described silicon chip;
Step 03: stop passing into described reactant gases, utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 04: start to input remote plasma in described reaction chamber, enters in described reaction chamber from described remote plasma generator remote plasma out through described remote plasma pipeline and described remote plasma entrance;
Step 05: described remote plasma drives away the impurity that described atomic level surface deposits;
Step 06: stop the described remote plasma of input, and utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 07: step 02 described in recirculation is to described step 06, until described atomic shell reaches target thickness.
Preferably, described atomic layer deposition apparatus comprises remote plasma flow direction controller; Described step 05 comprises: utilize remote plasma flow direction controller control described remote plasma along described silicon chip surface and the direction parallel with described silicon chip surface flow, thus remove the impurity that described atomic level surface deposits.
Preferably, described remote plasma flow direction controller controls described remote plasma and flows in the horizontal direction.
Atomic layer deposition apparatus of the present invention and Atomic layer deposition method, by arranging remote plasma generator in atomic layer deposition apparatus, and remote plasma pipeline with matching and remote plasma entrance is set on reaction chamber, in the process of carrying out ald, make atomic layer deposition sum remote plasma go deimpurity process to circulate to carry out, thus the single or multiple lift atomic level surface of each deposition all can be cleaned, for follow-up ald provides clean surface, repeatedly after cyclic deposition, the atomic layer level thin film of desired thickness can be obtained, further, can also remote plasma flow direction controller be passed through, control remote plasma and flow along the direction that silicon chip surface is parallel, thus better remove the impurity of atomic level surface, further, utilize remote plasma to remove the impurity of atomic level surface, can avoid causing damage to atomic shell and silicon chip, as can be seen here, by the present invention, the impurity defect in atomic layer deposition process can be reduced, improve the cleanliness factor of atomic layer level thin film, and reduce the damage to atomic shell and silicon chip, atomic layer deposition apparatus of the present invention, can improve, reduce the cost of more exchange device on existing atomic layer deposition apparatus.
Accompanying drawing explanation
Fig. 1 is the structure iron of the reaction chamber of a preferred embodiment of the present invention
Fig. 2 is the schematic flow sheet of the Atomic layer deposition method of a preferred embodiment of the present invention
Embodiment
For making content of the present invention clearly understandable, below in conjunction with Figure of description, content of the present invention is described further.Certain the present invention is not limited to this specific embodiment, and the general replacement known by those skilled in the art is also encompassed in protection scope of the present invention.
As previously mentioned, in existing atomic layer deposition process, have impurity defect at atomic level surface, although improving technique overcomes this impurity defect, owing to being subject to the restriction of technological temperature, thus effectively can not remove the impurity of atomic level surface; Thus, the present invention has done improvement to existing Atomic layer deposition method and equipment, thus effectively can remove the impurity defect of atomic level surface, and avoids causing damage to atomic shell and silicon chip.
Atomic layer deposition apparatus of the present invention, can comprise any structure of existing atomic layer deposition apparatus; Such as, reaction chamber, air feed port and steam line, vacuum extractor; Atomic layer deposition apparatus of the present invention also comprises: remote plasma generator, remote plasma entrance and remote plasma pipeline; Remote plasma generator, for generation of remote plasma; Remote plasma entrance, is arranged on the cavity of reaction chamber, for inputting remote plasma in reaction chamber; Remote plasma pipeline, is connected remote plasma generator with remote plasma entrance, for being delivered to remote plasma ingress by from remote plasma generator remote plasma out.
Below with reference to accompanying drawing 1 and specific embodiment, atomic layer deposition apparatus of the present invention is described in further detail.It should be noted that, accompanying drawing all adopt simplify very much form, use non-ratio accurately, and only in order to object that is convenient, that clearly reach aid illustration the present embodiment.
In the present embodiment, referring to Fig. 1, is the structure iron of the reaction chamber of a preferred embodiment of the present invention;
The atomic layer deposition apparatus of the present embodiment, comprises reaction chamber 00, silicon chip clamping device 03, air feed port 01 and steam line, vacuum extractor, vacuum outlet 04, remote plasma generator, remote plasma entrance 02 and remote plasma pipeline; Wherein,
Silicon chip W is positioned on silicon chip clamping device 03;
Air feed port 01 is for passing into the reactant gases of ald, and it can be arranged at any position of the cavity of reaction chamber 00, in the present embodiment, is arranged in the sidewall of reaction chamber 00, as shown in Figure 1; Steam line can be provided with the device opening and closing steam line;
Vacuum outlet 04, is arranged on the sidewall of reaction chamber 00, relative with air feed port 01, so that extracted out by reactant gases.
Remote plasma generator, for generation of remote plasma;
Here, remote plasma generator can adopt existing remote plasma generator, because the principle of remote plasma generator can known to those skilled in the artly be known, here repeats no more.
Remote plasma entrance 02, is arranged on the cavity of reaction chamber 00, for inputting remote plasma in reaction chamber 00;
Here, the position of remote plasma entrance 02 can be arranged at the top of reaction chamber 00, bottom or sidewall, and in the present embodiment, remote plasma entrance 02 is selected to be arranged in the cavity on the top of reaction chamber 00, as shown in Figure 1; The reactant gases of ald enters from the sidewall of reaction chamber 00, and remote plasma enters from the top of reaction chamber 00; Like this, pass into reactant gases and remote plasma by alternate cycles, alternate cycles can carry out atomic layer deposition sum Impurity removal process, thus obtain clean atomic level surface.
In order to more effectively remove the atomic level surface impurity defect deposited, remote plasma flow direction controller can be set in atomic layer deposition apparatus, for control remote plasma along with silicon chip W surface and the direction parallel with silicon chip W surface flow, such as, silicon chip W is placed horizontally in reaction chamber, then control remote plasma along silicon chip W surface and for horizontal direction flow.
Remote plasma flow direction controller can utilize magnetic field or electric field to deflect to make remote plasma, and flows with certain speed; The flow velocity of remote plasma should so that injury of primary sublayer and silicon chip are not advisable.
Remote plasma pipeline, is connected remote plasma generator with remote plasma entrance 02, for being delivered to remote plasma entrance 02 by from remote plasma generator remote plasma out.
Here, one end of remote plasma pipeline is connected with remote plasma generator, the other end is connected with the remote plasma entrance 02 on reaction chamber, that is to say that remote plasma generator is connected with remote plasma entrance 02 by remote plasma pipeline.Remote plasma install pipeline can have multiple method, such as, adopts pipe as remote plasma pipeline, arranges hole and form remote plasma pipeline etc. in atomic layer deposition apparatus.Remote plasma pipeline can be provided with the device opening and closing remote plasma pipeline, such as valve etc.
Atomic layer deposition apparatus of the present invention, can improve on existing atomic layer deposition apparatus, avoids the cost increase that more exchange device causes.
Below with reference to accompanying drawing 2 and specific embodiment, Atomic layer deposition method of the present invention is described in further detail.It should be noted that, accompanying drawing all adopt simplify very much form, use non-ratio accurately, and only in order to object that is convenient, that clearly reach aid illustration the present embodiment.
Referring to Fig. 2, is the schematic flow sheet of the Atomic layer deposition method of a preferred embodiment of the present invention; The Atomic layer deposition method of the present embodiment adopts atomic layer deposition apparatus of the present invention, and it comprises the following steps:
Step 01: silicon chip is placed in reaction chamber, and utilize vacuum extractor that reaction chamber is evacuated to vacuum state;
Concrete, vacuum extractor can adopt the existing vaccum-pumping equipments such as vacuum pump, repeats no more here.When vacuumizing, gas can be discharged from the air vout reaction chamber; Vacuum state should be the vacuum condition required for existing ald, such as, 10
-4-10
-6between Pa.
Step 02: start to pass into reactant gases, reactant gases enters in reaction chamber through steam line and air feed port, at the surface deposition single or multiple lift atomic shell of silicon chip;
Concrete, can by opening the steam supply valve of steam line or opening reacting gas source and pass into reactant gases; The atomic shell deposited at silicon chip surface can be single or multiple lift, this will arrange the number of plies of deposition according to the target thickness of sublayer, actual process Central Plains, certainly, the thickness of multi-layer atomic layer is here far smaller than target thickness, otherwise, can only by the Impurity removal of atomic shell most surface, and impurity is wrapped in the object that atomic shell inside just effectively can not reach repeatedly circulation removal atomic shell impurity defect.
Step 03: stop passing into reactant gases, utilize vacuum unit that reaction chamber is evacuated to vacuum state;
Concrete, can stop passing into reactant gases by the steam supply valve or off-response gas source of closing steam line; Here vacuum state can 10
-4-10
-6between Pa.
Step 04: start to input remote plasma in reaction chamber, enters in reaction chamber from remote plasma generator remote plasma out through remote plasma pipeline and remote plasma entrance;
Concrete, remote plasma generator can be opened at this moment, if remote plasma pipeline is provided with the device that valve etc. controls keying, then can correspondingly be opened;
Step 05: remote plasma drives away the impurity that atomic level surface deposits;
Concrete, in order to remove the impurity defect of the atomic level surface deposited better, remote plasma flow direction controller can be utilized to control described remote plasma along silicon chip surface and the flowing of parallel with silicon chip surface direction, thus remove the impurity that atomic level surface deposits; Such as, silicon wafer horizontal place, then can control remote plasma along silicon chip surface and for horizontal direction flow.The flow velocity of remote plasma should be suitable, should not damage atomic shell and silicon chip is advisable.
Step 06: stop input remote plasma, and utilize vacuum unit that reaction chamber is evacuated to vacuum state;
Concrete, can pass through to close the headstock gear such as valve on remote plasma pipeline, or closedown remote plasma generator stops inputting remote plasma.
Step 07: recirculation step 02 is to step 06, until atomic shell reaches target thickness.
Concrete, in order to make atomic shell reach target thickness, need constantly repeatedly to carry out ald; Have clean atomic level surface in order to during ald in next circulation, the removal process of remote plasma is also alternately entrained in atomic layer deposition process of each circulation, that is to say that recirculation step 02 is to step 06; Target thickness can require to set according to actual process.
Atomic layer deposition method of the present invention can be applied in any thin film deposition processes, and such as, atom layer deposition process is used for the dielectric film etc. prepared in metal gate.
In sum, by the present invention, the impurity defect in atomic layer deposition process can be reduced, improve the cleanliness factor of atomic layer level thin film, and reduce the damage to atomic shell and silicon chip; Atomic layer deposition apparatus of the present invention, can improve, reduce the cost of more exchange device on existing atomic layer deposition apparatus.
Although the present invention discloses as above with preferred embodiment; right described embodiment is citing for convenience of explanation only; and be not used to limit the present invention; those skilled in the art can do some changes and retouching without departing from the spirit and scope of the present invention, and the protection domain that the present invention advocates should be as the criterion with described in claims.
Claims (6)
1. an atomic layer deposition apparatus, comprises reaction chamber, air feed port and steam line, vacuum extractor, it is characterized in that, described atomic layer deposition apparatus also comprises:
Remote plasma generator, for generation of remote plasma;
Remote plasma entrance, is arranged on the cavity of described reaction chamber, for inputting remote plasma in described reaction chamber;
Remote plasma pipeline, is connected described remote plasma generator with described remote plasma entrance, for being delivered to described remote plasma ingress by from described remote plasma generator remote plasma out.
2. atomic layer deposition apparatus according to claim 1, it is characterized in that, described atomic layer deposition apparatus also comprises: remote plasma flow direction controller, for control described remote plasma along silicon chip surface and the direction parallel with described silicon chip surface flow.
3. atomic layer deposition apparatus according to claim 2, is characterized in that, described remote plasma flow direction controller, controls described remote plasma and flow in the horizontal direction.
4. the Atomic layer deposition method adopting atomic layer deposition apparatus according to claim 1 to carry out, is characterized in that, comprising:
Step 01: silicon chip is placed in described reaction chamber, and utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 02: start to pass into described reactant gases, described reactant gases enters in described reaction chamber through described steam line and air feed port, at the surface deposition single or multiple lift atomic shell of described silicon chip;
Step 03: stop passing into described reactant gases, utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 04: start to input remote plasma in described reaction chamber, enters in described reaction chamber from described remote plasma generator remote plasma out through described remote plasma pipeline and described remote plasma entrance;
Step 05: described remote plasma drives away the impurity that described atomic level surface deposits;
Step 06: stop the described remote plasma of input, and utilize described vacuum unit that described reaction chamber is evacuated to vacuum state;
Step 07: step 02 described in recirculation is to described step 06, until described atomic shell reaches target thickness.
5. Atomic layer deposition method according to claim 4, is characterized in that, described atomic layer deposition apparatus comprises remote plasma flow direction controller; Described step 05 comprises: utilize remote plasma flow direction controller control described remote plasma along described silicon chip surface and the direction parallel with described silicon chip surface flow, thus remove the impurity that described atomic level surface deposits.
6. Atomic layer deposition method according to claim 5, is characterized in that, described remote plasma flow direction controller controls described remote plasma and flows in the horizontal direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410487817.6A CN104233227A (en) | 2014-09-23 | 2014-09-23 | Atomic layer deposition equipment and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410487817.6A CN104233227A (en) | 2014-09-23 | 2014-09-23 | Atomic layer deposition equipment and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104233227A true CN104233227A (en) | 2014-12-24 |
Family
ID=52222105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410487817.6A Pending CN104233227A (en) | 2014-09-23 | 2014-09-23 | Atomic layer deposition equipment and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104233227A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105506581A (en) * | 2015-12-15 | 2016-04-20 | 北京七星华创电子股份有限公司 | Realization method for film preparation by applying atomic layer deposition technology |
| CN106356327A (en) * | 2016-11-18 | 2017-01-25 | 上海华力微电子有限公司 | Device for reducing growth of back of wafer |
| CN114622183A (en) * | 2020-12-11 | 2022-06-14 | 湖南红太阳光电科技有限公司 | Method for preparing silicon oxide film |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020197828A1 (en) * | 2001-06-21 | 2002-12-26 | Hitachi Kokusai Electric Inc. | Method and apparatus for manufacturing a semiconductor device and processing a substrate |
| US20060014384A1 (en) * | 2002-06-05 | 2006-01-19 | Jong-Cheol Lee | Method of forming a layer and forming a capacitor of a semiconductor device having the same layer |
| US20090011150A1 (en) * | 2004-08-04 | 2009-01-08 | Hyeong-Tag Jeon | Remote Plasma Atomic Layer Deposition Apparatus and Method Using Dc Bias |
| CN101395297A (en) * | 2006-02-28 | 2009-03-25 | 东京毅力科创株式会社 | Methods of depositing ruthenium film and memory medium readable by computer |
| CN102892922A (en) * | 2010-03-17 | 2013-01-23 | 应用材料公司 | Method and apparatus for remote plasma source assisted silicon-containing film deposition |
-
2014
- 2014-09-23 CN CN201410487817.6A patent/CN104233227A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020197828A1 (en) * | 2001-06-21 | 2002-12-26 | Hitachi Kokusai Electric Inc. | Method and apparatus for manufacturing a semiconductor device and processing a substrate |
| US20060014384A1 (en) * | 2002-06-05 | 2006-01-19 | Jong-Cheol Lee | Method of forming a layer and forming a capacitor of a semiconductor device having the same layer |
| US20090011150A1 (en) * | 2004-08-04 | 2009-01-08 | Hyeong-Tag Jeon | Remote Plasma Atomic Layer Deposition Apparatus and Method Using Dc Bias |
| CN101395297A (en) * | 2006-02-28 | 2009-03-25 | 东京毅力科创株式会社 | Methods of depositing ruthenium film and memory medium readable by computer |
| CN102892922A (en) * | 2010-03-17 | 2013-01-23 | 应用材料公司 | Method and apparatus for remote plasma source assisted silicon-containing film deposition |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105506581A (en) * | 2015-12-15 | 2016-04-20 | 北京七星华创电子股份有限公司 | Realization method for film preparation by applying atomic layer deposition technology |
| CN106356327A (en) * | 2016-11-18 | 2017-01-25 | 上海华力微电子有限公司 | Device for reducing growth of back of wafer |
| CN114622183A (en) * | 2020-12-11 | 2022-06-14 | 湖南红太阳光电科技有限公司 | Method for preparing silicon oxide film |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10619247B2 (en) | Substrate processing apparatus, injector, and substrate processing method | |
| US10655218B2 (en) | Substrate processing apparatus, method of manufacturing semiconductor device, and recording medium | |
| CN104947082B (en) | Gas supply mechanism and method for supplying gas and use its film formation device and film build method | |
| KR101880516B1 (en) | Substrate processing apparatus, method of manufacturing semiconductor device and non-transitory computer-readable recording medium | |
| US7731797B2 (en) | Substrate treating apparatus and semiconductor device manufacturing method | |
| JP2013033965A (en) | Substrate processing apparatus, substrate processing facility, and substrate processing method | |
| US11018033B2 (en) | Substrate processing apparatus, method of manufacturing semiconductor device, and recording medium | |
| KR19990063409A (en) | Heat treatment equipment | |
| KR20170026036A (en) | Substrate processing apparatus, method of manufacturing semiconductor device and non-transitory computer-readable recording medium | |
| US20120220116A1 (en) | Dry Chemical Cleaning For Semiconductor Processing | |
| US20170183770A1 (en) | Substrate processing apparatus | |
| WO2006137287A1 (en) | Method for fabricating semiconductor device and equipment for processing substrate | |
| US11054184B2 (en) | Methods and apparatus for processing a substrate to remove moisture and/or residue | |
| CN104233227A (en) | Atomic layer deposition equipment and method | |
| KR101896746B1 (en) | Method of driving vertical heat treatment apparatus, recording medium, and vertical heat treatment apparatus | |
| JP2014199856A (en) | Method for operating vertical heat treatment device, storage medium, and vertical heat treatment device | |
| US9373498B2 (en) | Method of operating vertical heat treatment apparatus, vertical heat treatment apparatus and non-transitory recording medium | |
| KR100905262B1 (en) | Substrate Processing Apparatus and Manufacturing Method for a Semiconductor Device | |
| US20150369539A1 (en) | Apparatus for processing substrate | |
| US9171724B2 (en) | Substrate processing apparatus and method for manufacturing semiconductor device | |
| TW201327705A (en) | Substrate processing apparatus, substrate processing method and storage medium | |
| JP6793903B2 (en) | Annealing method, processing chamber, and annealing equipment | |
| US20180312967A1 (en) | Substrate processing apparatus, method of removing particles in injector, and substrate processing method | |
| TWI532967B (en) | Apparatus for processing substrate | |
| WO2007020926A1 (en) | Method for surface treating semiconductor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20141224 |