DK173655B1 - Method of depositing layers on a substrate - Google Patents
Method of depositing layers on a substrate Download PDFInfo
- Publication number
- DK173655B1 DK173655B1 DK199901642A DKPA199901642A DK173655B1 DK 173655 B1 DK173655 B1 DK 173655B1 DK 199901642 A DK199901642 A DK 199901642A DK PA199901642 A DKPA199901642 A DK PA199901642A DK 173655 B1 DK173655 B1 DK 173655B1
- Authority
- DK
- Denmark
- Prior art keywords
- substrate
- carrier
- pecvd
- chamber
- support
- Prior art date
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Classifications
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/458—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for supporting substrates in the reaction chamber
- C23C16/4582—Rigid and flat substrates, e.g. plates or discs
- C23C16/4583—Rigid and flat substrates, e.g. plates or discs the substrate being supported substantially horizontally
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/50—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges
- C23C16/505—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using radio frequency discharges
- C23C16/509—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using radio frequency discharges using internal electrodes
- C23C16/5096—Flat-bed apparatus
Description
DK 173655 B1DK 173655 B1
Den foreliggende opfindelse vedrører en fremgangsmåde til deponering af lag, f.eks. ved Plasma Enhanced Chemical Vapour Deposition (PECVD), på et substrat, idet fremgangsmåden omfatter placering af substratet mellem en øvre elektrode og en nedre elektrode.The present invention relates to a method for depositing layers, e.g. by Plasma Enhanced Chemical Vapor Deposition (PECVD), on a substrate, the method comprising placing the substrate between an upper electrode and a lower electrode.
55
Teknikkens stadeState of the art
Ved anvendelse af et PECVD-deponeringskammer med parallel plade ender en stor del af det deponerede materiale på kammerets vægge og elektroderne.Using a parallel plate PECVD deposition chamber, much of the deposited material ends up on the chamber walls and the electrodes.
10 Dette medfører en ændring i systemets impedans og ændrer derfor de deponerede films egenskaber en lille smule. Ved mange applikationer er dette ikke noget problem, men ved bølgelederproduktion, hvor en nøje kontrol af brydningsindekset er vigtig, kan dette medføre ikke-reproducerbare resultater.10 This causes a change in the system impedance and therefore slightly changes the properties of the deposited films. In many applications this is not a problem, but in waveguide production, where close control of the refractive index is important, this can lead to non-reproducible results.
15 Det er derfor vigtigt at rense kammeret regelmæssigt. Dette kan ske enten ved en mekanisk rensning eller en kemisk rensning in situ. Den kemiske rensning er en speciel plasmaproces, der anvendes til ætsning af det deponerede lag.15 It is therefore important to clean the chamber regularly. This can be done either by mechanical cleaning or chemical cleaning in situ. The chemical purification is a special plasma process used to etch the deposited layer.
En fordel ved den kemiske renseproces er, at den udføres uden at skille syste-20 met ad, hvorved den tid, hvor kammeret er ude af drift, reduceres. Der er imidlertid ved processen et problem med forskellige ætsningsgrader på forskellige overflader. Især er ætsningsgraden på den spændingsførende elektrode cirka en faktor to større end på den jordede elektrode. Derfor bliver den strømførende elektrode renset først.An advantage of the chemical purification process is that it is performed without separating the system, thereby reducing the time the chamber is out of operation. However, in the process there is a problem with different etching rates on different surfaces. In particular, the etching rate on the live electrode is approximately one factor two greater than on the grounded electrode. Therefore, the live electrode is cleansed first.
2525
Kammerets aluminiumsvægge udsættes for plasmaet, når alt det deponerede glas er blevet flernet. En fortsættelse af renseprocessen herefter vil medføre en dannelse af et poiymeriag. Da renseprocessen ikke stopper, før den jordede elektrode er renset, vil der blive dannet et ret tykt polymerlag på den spæn-30 dingsførende elektrode.The aluminum walls of the chamber are exposed to the plasma when all the deposited glass has been removed. A continuation of the purification process thereafter will result in the formation of a polymer layer. Since the cleaning process does not stop until the grounded electrode is cleaned, a fairly thick polymer layer will be formed on the live conducting electrode.
2 DK 173655 B12 DK 173655 B1
Et polymerlag vil også straks blive dannet på den jordede elektrode på det sted, hvor waferen har ligget, eftersom der ikke er deponeret glas her. Efter renseprocessen er kammeret derfor delvis rent og delvist dækket af polymerer. Disse polymerer vil påvirke deponeringsprocessen på en række måder.A polymer layer will also be formed immediately on the grounded electrode at the location of the wafer since no glass is deposited here. Therefore, after the purification process, the chamber is partially clean and partially covered with polymers. These polymers will affect the deposition process in a number of ways.
55
For det første er det deponerede glas efter nogen tid tilbøjelig til at skalle af polymerlaget, hvilket medfører en partikelkontaminering i kammeret. Dette vil påvirke filmkvaliteten.First, after some time, the deposited glass tends to peel off the polymer layer, causing a particle contamination in the chamber. This will affect the film quality.
10 For det andet er polymerernes lagtykkelse på den jordede elektrode ikke nødvendigvis den samme fra gang til gang. Følgelig vil miljøet for wafeme ikke være det samme imellem forskellige deponeringer og renseperioder. Anvendelse af forskellige substratstørrelser vil heller ikke være muligt; f.eks. vil deponering på en 5"-wafer efter en 4"-wafer resultere i et anderledes miljø ved yderdelen af 5"-15 waferen sammenlignet med den midterste 4"-deLSecondly, the layer thickness of the polymers on the ground electrode is not necessarily the same from time to time. Consequently, the environment for the wafeme will not be the same between different deposits and cleaning periods. Use of different substrate sizes will also not be possible; eg. depositing a 5 "wafer after a 4" wafer will result in a different environment at the outer portion of the 5 "-15 wafer compared to the middle 4" wafer
Følgelig skal to problemer løses: 1) Kammerbetingelseme skal være reproducerbare og stabile under en depo- 20 neringscyklus, og 2) renseprocessen skal frembringe så få polymerer som muligt.Accordingly, two problems must be solved: 1) The chamber conditions must be reproducible and stable during a deposition cycle, and 2) the purification process must produce as few polymers as possible.
Endelig skal renseprocessen være så kort som mulig for at øge systemets drifts-25 tid.Finally, the cleaning process should be as short as possible to increase system operating time.
Kendt teknikPrior art
Den britiske patentansøgning GB 2312439 beskriver en fremgangsmåde til de-30 ponering af lag ved PECVD til fremstilling af optiske bølgeledere. Det anføres, at der opnås en større regenereringsmulighed og kontrol af/med brydningsindekset 3 DK 173655 B1 ved placering af substratet på den spændingsførende elektrode og derved bibeholdelse af en negativ forspænding (bias) på substratet under deponeringen. Der anføres intet om, hvorledes man undgår uønsket dannelse af lag af deponeret materiale på elektroderne, renseprocedurer, hvorledes man undgår dannelse af 5 polymerer under rensningen eller generelt, hvorledes man øger kammerets driftstid og stabile kammerbetingelser.British Patent Application GB 2312439 discloses a method for depositing layers by PECVD for the production of optical waveguides. It is stated that greater regeneration capability and control of / with the refractive index 3 DK 173655 B1 is obtained by placing the substrate on the live electrode, thereby maintaining a negative bias (bias) on the substrate during deposition. There is no mention of how to avoid unwanted formation of layers of deposited material on the electrodes, cleaning procedures, how to avoid formation of 5 polymers during the cleaning, or in general how to increase chamber operating time and stable chamber conditions.
Beskrivelse af opfindelsen 10 Det er et formål med den foreliggende opfindelse at tilvejebringe en fremgangsmåde til forbedring af stabiliteten og reproducerbarheden af kammerbetingelserne i en PECVD-reaktor til fremstilling af silicabaserede, plane bølgelederkom-ponenter. Det er et yderligere formål med opfindelsen, at de kemiske plasmarenseprocesser, der anvendes til Qemelse af uønskede deponeringer af silica (Si02) 15 på kammervæggene, frembringer så få polymerer som muligt. Endelig er det et formål med den foreliggende opfindelse, at renseprocessen skal være så kort som mulig for derved at bidrage til en forøgelse af systemets driftstid.DESCRIPTION OF THE INVENTION It is an object of the present invention to provide a process for improving the stability and reproducibility of the chamber conditions in a PECVD reactor for the production of silica-based planar waveguide components. It is a further object of the invention that the chemical plasma cleaning processes used to remove unwanted deposits of silica (SiO 2) 15 on the chamber walls produce as few polymers as possible. Finally, it is an object of the present invention for the purification process to be as short as possible thereby contributing to an increase in system operating time.
Ifølge opfindelsen tilvejebringes der en fremgangsmåde, som er defineret i ind-20 ledningen til krav 1. Denne fremgangsmåde er kendetegnet ved, at substratet placeres på en bærer, som er anbragt på den nedre elektrode.According to the invention, there is provided a method as defined in the preamble of claim 1. This method is characterized in that the substrate is placed on a support disposed on the lower electrode.
På denne måde er det muligt at reducere ude-af-drift-tiden i Plasma Enhanced Chemical Vapour Deposition (PECVD) -reaktorer, når de f.eks. anvendes til 25 fremstilling af silicabaserede, planare bølgelederkomponenter. Ved anvendelse af fremgangsmåden forbliver PECVD-reaktoren i en ensartet og veikontrolleret tilstand i længere tidsperioder, som medfører en større kapacitet ved de anvendte deponeringsprocesser.In this way, it is possible to reduce the out-of-operation time in Plasma Enhanced Chemical Vapor Deposition (PECVD) reactors when, e.g. used for the manufacture of silica-based, planar waveguide components. Using the method, the PECVD reactor remains in a uniform and road-controlled state for extended periods of time, resulting in greater capacity in the landfill processes used.
30 Hensigtsmæssige udførelsesformer for opfindelsen er skitseret i krav 2-8.Suitable embodiments of the invention are outlined in claims 2-8.
4 DK 173655 B14 DK 173655 B1
Opfindelsen vil i det følgende blive beskrevet ved hjælp af et eksempel under henvisning til den eneste figur, som viser en principkonstruktion af de indvendige dele af et vandretliggende PECVD-kammer med parallel plade.The invention will be described in the following by way of example with reference to the only figure which shows a principle construction of the inner parts of a horizontal plate with a parallel plate PECVD.
5 På tegningen er de indvendige dele af et vandretliggende PECVD-kammer med parallel plade med nedre og øvre elektrode angivet 1 hhv. 2. Som det fremgår, placeres et substrat 4 på en bæreplade 3, såsom en stor smeltet kvartsbærer 3. Diameteren af den smeltede kvartsbærer 3 bør svare til diameteren af den nedre elektrode 1 for at holde den fri for uønsket, deponeret materiale. Stoporganer 5 10 holder substratet 4 i den angivne stilling på bærepladen 3 under isætning og udtagning og under behandlingen.5 In the drawing, the inner parts of a horizontal PECVD chamber with parallel plate with lower and upper electrode are indicated 1 and 1 respectively. 2. As can be seen, a substrate 4 is placed on a support plate 3, such as a large molten quartz support 3. The diameter of the molten quartz support 3 should correspond to the diameter of the lower electrode 1 to keep it free of unwanted deposited material. Stop means 5 10 hold the substrate 4 in the indicated position on the support plate 3 during loading and unloading and during processing.
Virkningen af den smeltede kvartsbærer 3 vil nu blive forklaret: 15 Ved at placere waferen 4 på en bærer 3 af et materiale svarende til laget depo neret i PECVD-kammeret, vil systemets impedans blive mindre påvirket af det deponerede materiale. Deponering på forskellige substratstørreiser 4 kan ske enten ved at anvende den samme smeltede kvartsbærer 3 eller en anden bærer 3.The effect of the molten quartz support 3 will now be explained: 15 By placing the wafer 4 on a support 3 of a material similar to the layer deposited in the PECVD chamber, the impedance of the system will be less affected by the deposited material. Deposition on different substrate size travels 4 can be done using either the same molten quartz support 3 or another carrier 3.
2020
Også renseprocessen udføres med en smeltet kvartsbærer 3. Renseprocessen stoppes da, så snart den spændingsførende elektrode 2 er blevet renset. Herved undgås næsten fuldstændigt polymerdannelse.The cleaning process is also performed with a molten quartz support 3. The cleaning process is then stopped as soon as the live electrode 2 has been cleaned. This avoids almost complete polymer formation.
25 Den mest betydningsfulde fordel ved fremgangsmåden er den forøgede driftstid af PECVD-deponeringssystemet. Producenter af PECVD-udstyr anbefaler en plasmarensning for hver 5-6 pm deponeret materiale. Dette ville gøre bølgele-derfremstilling så godt som umulig, da de enkelte lag består af 4 til 15 pm glas. Endvidere svarer den anbefalede rensetid til deponeringstiden.The most significant advantage of the method is the increased operating time of the PECVD landfill system. Manufacturers of PECVD equipment recommend a plasma cleaning for every 5-6 pm deposited material. This would make waveguide making virtually impossible as the individual layers consist of 4 to 15 µm glass. Furthermore, the recommended cleaning time corresponds to the deposition time.
30 5 DK 173655 B130 5 DK 173655 B1
Ved anvendelse af fremgangsmåden ifølge opfindelsen er det muligt at deponere op til 200 pm silicaglas, før en plasmarensning er nødvendig.Using the method of the invention, it is possible to deposit up to 200 µm of silica glass before plasma cleaning is necessary.
En yderligere fordel er forbedret reproducerbarhed. Det deponerede materiale 5 opfører sig meget lig den smeltede kvartsbærer 3, og derfor vil plasmamiljøet ikke ændre sig ved deponeringer.An additional benefit is improved reproducibility. The deposited material 5 behaves very similar to the molten quartz carrier 3, and therefore the plasma environment will not change upon deposition.
Polymerdannelsen i kammeret reduceres også dramatisk. Dette medfører en væsentlig bedre glaskvalitet end med traditionelle metoder.The polymer formation in the chamber is also dramatically reduced. This results in significantly better glass quality than with traditional methods.
1010
Mange typer bærere kan anvendes, men det foretrækkes sædvanligvis, at såvel de dielektriske egenskaber som varmeegenskabeme for bærematerialet svarer til de dielektriske egenskaber og varmeegenskabeme for materialet, som deponeres i PECVD-kammeret. Hvis silica eller overfladebehandlet silica således de-15 poneres til fremstilling af plane bølgeledere, foretrækkes en smeltet kvartsbærer.Many types of supports can be used, but it is usually preferred that both the dielectric properties and the heat properties of the support material correspond to the dielectric properties and heat properties of the material deposited in the PECVD chamber. Thus, if silica or surface-treated silica is deposited to produce planar waveguides, a molten quartz support is preferred.
(Herved forstås kvarts, som smelter over et kort tidsrum, så det Ikke længere er krystallinsk - "fused silicia”.)(This means quartz, which melts over a short period of time, so that it is no longer crystalline - "fused silicia".)
Fortrinsvis er bæreren forsynet med midler til at holde waferen på plads, når 20 waferen på bæreren isættes eller udtages af PECVD-kammeret og under behandlingen. I en udførelsesform består midlerne til positionering af waferen af en fordybning i bæreren, som passer til waferen. I en anden udførelsesform er stoporganer anbragt på bæreren for at holde waferen på plads.Preferably, the carrier is provided with means for holding the wafer in place as the 20 wafer on the carrier is inserted or removed by the PECVD chamber and during processing. In one embodiment, the means for positioning the wafer consists of a recess in the carrier which fits the wafer. In another embodiment, stop means are provided on the carrier to hold the wafer in place.
Claims (8)
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK199901642A DK173655B1 (en) | 1999-11-15 | 1999-11-15 | Method of depositing layers on a substrate |
| AU13822/01A AU1382201A (en) | 1999-11-15 | 2000-11-15 | A method for depositing layers on a substrate |
| EP00975836A EP1248866A1 (en) | 1999-11-15 | 2000-11-15 | A method for depositing layers on a substrate |
| PCT/DK2000/000634 WO2001036708A1 (en) | 1999-11-15 | 2000-11-15 | A method for depositing layers on a substrate |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK164299 | 1999-11-15 | ||
| DK199901642A DK173655B1 (en) | 1999-11-15 | 1999-11-15 | Method of depositing layers on a substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DK199901642A DK199901642A (en) | 2001-05-16 |
| DK173655B1 true DK173655B1 (en) | 2001-05-28 |
Family
ID=8106816
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK199901642A DK173655B1 (en) | 1999-11-15 | 1999-11-15 | Method of depositing layers on a substrate |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP1248866A1 (en) |
| AU (1) | AU1382201A (en) |
| DK (1) | DK173655B1 (en) |
| WO (1) | WO2001036708A1 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4060660A (en) * | 1976-01-15 | 1977-11-29 | Rca Corporation | Deposition of transparent amorphous carbon films |
| JPS6092477A (en) * | 1983-10-27 | 1985-05-24 | Matsushita Electric Ind Co Ltd | Chemical treatment device using plasma |
| US4681653A (en) * | 1984-06-01 | 1987-07-21 | Texas Instruments Incorporated | Planarized dielectric deposited using plasma enhanced chemical vapor deposition |
| FR2584101B1 (en) * | 1985-06-26 | 1987-08-07 | Comp Generale Electricite | DEVICE FOR MANUFACTURING AN OPTICAL COMPONENT WITH A REFRACTION INDEX GRADIENT |
| FR2653633B1 (en) * | 1989-10-19 | 1991-12-20 | Commissariat Energie Atomique | CHEMICAL TREATMENT DEVICE ASSISTED BY A DIFFUSION PLASMA. |
| JPH0710689A (en) * | 1993-06-17 | 1995-01-13 | Furukawa Electric Co Ltd:The | Device for growth of semiconductor in gaseous phase |
| US5763020A (en) * | 1994-10-17 | 1998-06-09 | United Microelectronics Corporation | Process for evenly depositing ions using a tilting and rotating platform |
-
1999
- 1999-11-15 DK DK199901642A patent/DK173655B1/en not_active IP Right Cessation
-
2000
- 2000-11-15 WO PCT/DK2000/000634 patent/WO2001036708A1/en not_active Application Discontinuation
- 2000-11-15 AU AU13822/01A patent/AU1382201A/en not_active Abandoned
- 2000-11-15 EP EP00975836A patent/EP1248866A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| EP1248866A1 (en) | 2002-10-16 |
| DK199901642A (en) | 2001-05-16 |
| AU1382201A (en) | 2001-05-30 |
| WO2001036708A1 (en) | 2001-05-25 |
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