WO2010004006A2

WO2010004006A2 - Device and method for impressing structures in a substrate, in particular in optical data storage media, semiconductor structures and microstructures

Info

Publication number: WO2010004006A2
Application number: PCT/EP2009/058758
Authority: WO
Inventors: Michael Reising; Stefan Kempf
Original assignee: Singulus Technologies Ag
Priority date: 2008-07-10
Filing date: 2009-07-09
Publication date: 2010-01-14
Also published as: WO2010004006A3; WO2010004006A9

Abstract

In the manufacture of optical data storage media, data structures are impressed into the substrate (2) in a protective chamber under vacuum. The impression head (4) forms the chamber cover through a flexible seal (20, 21) between the impression head (4) and the support (1) holding the substrate (2) to be impressed. This enables the chamber volume to be reduced and thus low pumping and cycle times as well as good access by the impression head (4). In addition, a self-sealing coupling can be used in the supply canal (101 to 105) between the chamber and the working pressure generating device (100). This makes it possible to quickly exchange the stamper (3) attached to the impression head (4) as a result of the good accessibility of the chamber interior.

Description

Device and method for embossing structures in a substrate, in particular in optical data carriers, semiconductor structures and

microstructures

The invention relates to a device and a method for embossing structures in a substrate under protected conditions, as used in particular in optical data carriers, semiconductor structures and microstructures.

The production of optical data carriers (eg CD, DVD) typically involves an embossing process for embossing data structures into the substrate. To the embossed substrate free of unwanted inclusions, z. B. air bubbles, to hold the stamping process takes place under vacuum or vacuum. Conventional embossing plants realize the negative pressure by means of a largely tight chamber which completely encloses at least the compulsory directly involved components of the embossing device. These components comprise the embossing head with the stamper attached thereto, the part of the typically flat, smooth support opposite this embossing head, and the moldable substrate which is injected or inserted prior to the embossing and which is e.g. B. is typically made of polycarbonate in the case of optical data carriers. The carrier serves as a base and z. B. formed by a stable glass plate. The surface of the punch, which is held on the embossing head, has many smallest projections, which serve as a negative for the introduced into the blank pits, whose arrangement represents the fixed data on the data carrier.

The conventional embossing in a chamber at low pressure is z. For example, in J PA-1-101126, US 5,078,947 A and DE 22 63 712 A described. From DE 101 00 426 B4 an apparatus for joining two substrates in a closed chamber is described; in this known device, the plate carrying a substrate is connected to a flexible membrane and supported by it floating relative to the other plate. The movement of Floating plate is done by adjusting the pressure difference on opposite side of the membrane. A controlled embossing process is not possible with such a movement course.

Fig. 1 shows schematically a conventional embossing device. The carrier 1 is z. B. formed by a central, enclosed in a metal frame glass plate. The carrier is typically planar and configured such that a moldable substrate 2 can be applied to its surface. In these inserted between the punch 3 and the carrier 1 substrate blank 2, the information structures are impressed during the embossing process 2. The punch 3 is located directly on the embossing head 4, which is located entirely within the chamber, which is formed by the chamber lid 5 and the carrier 1. The embossing head 4 is held, guided and moved by means of an external lifting slide device (not shown) via lifting axles 6. These lifting axles 6 are guided through gas-tight sliding bushings 31 through the chamber lid 5. The number and position of the Hubachsen 6 is variable, but these axes should be distributed as symmetrical as possible for stability reasons. An optimum represent three axes or a central axis.

Both these sliding bushings 31, as well as the passages 30 for the supply ports 7 to 9 are sealed and movable through the chamber lid. 5

The necessary negative pressure for sucking the punch 3 to the embossing head 4, can be generated via the line 7, and the air discharged, are. Within the chamber, a vacuum or vacuum can be generated by means of a vacuum generating device 100 or pumping arrangement. This vacuum region 10 is formed by the chamber described above and the sealing surface 11 with sealing ring 12.

The chamber can be opened along the sealing surface 11, which corresponds to the contact surface of the carrier 1 and chamber lid 5, z. The chamber lid 5 (also upper section of the chamber) is vertically (see arrow A - parallel to the embossing force and center axis Z) movable to create a horizontal space along the open sealing surface 11 or to close this. After closing, a negative pressure can be generated in the pressure chamber, ie in a device according to FIG. 1, the upper section of the pressure chamber must again be placed along the sealing surface 11. The closed chamber also protects against external influences, such. As impurities, dust or light, regardless of whether in the chamber a certain working pressure is maintained.

Via optional additional supply connections, a blank adhering to the stamp 3 after embossing can be removed by applying pressure. The required relative to the chamber lid 5 movable supply ports 7 (and possibly existing other lines) require sliding bushings 30, which represent additional wearing parts and additional leaks. This applies in particular also to the sliding bushings 31 of the lifting axles 6.

The embossing chamber 10 is connected to a vacuum generating device 100 via a flexible feed. A short movement of the chamber lid is necessary because the chamber must be opened to remove the embossed blank. The underside of the chamber forming the carrier 1 is usually formed as a glass plate on a turntable which is temporarily covered with the substrate to be embossed. Therefore, the bottom of the chamber is not suitable for connections for sucking the air. A movable air suction duct (vacuum supply) was therefore realized by means of a flexible hose attached to the chamber lid. This requires a complex installation of the air suction and complicates a complete chamber opening, z. B. for service purposes or to change stamper.

It is an object of the present invention to accelerate operation and / or maintenance. This object is achieved with the features of the claims.

In the solution of the problem, the invention proceeds from the basic idea of forming the chamber lid as an embossing head and / or to use a self-closing connection for the vacuum connection. This is made possible by a deformable sealing between the embossing head and the substrate carrier or by a separable self-sealing vacuum coupling in the vacuum channel.

According to the invention can be dispensed with the movable, wear-intensive vacuum feedthroughs. The attachment of the lifting axis and the optional supply connections takes place directly on the embossing head. The supply connections can z. B. for discharging air for sucking the stampers to the embossing head or the blowing off of the embossed substrate serve by the stamper.

The supply connections and the stroke axis or the stroke axes can be arranged on the atmosphere side and fixed to the embossing head. The seal diaphragm allows relative movement between the outer ring flange and the stamping head with punch during the embossing stroke. The solution according to the invention is inexpensive and allows good accessibility for service purposes. In addition, the volume to be evacuated, the surfaces exposed to the vacuum in the interior of the vacuum chamber as well as narrow gaps, which can only be evacuated poorly, are significantly reduced compared to the prior art (see FIG. This reduces the required pumping time for vacuum generation and thus the production cycle time, thus increasing productivity.

The vacuum coupling according to the invention allows the use of stationary vacuum shut-off valves. The spring-loaded contact head moves along with the chamber lid or the outer annular flange during the entire process, wherein the vacuum connection takes place via a flexible connection in the axial direction of the vacuum channel. For a stamper change or for service purposes on the embossing head no tools and no additional drive for the separation or connection process of the vacuum coupling are required. When retracting the embossing head, the vacuum connection is automatically disconnected. After a pivoting movement, z. B. by 90 °, the embossing head velvet Stamper is comfortable from the side, z. B. for maintenance purposes, fully accessible. The invention will be explained in more detail below with reference to the drawings; show it:

1 shows schematically a conventional embossing device with the chamber closed, FIGS. 2a and 2b schematically embossing devices according to the invention with the chamber closed,

3a shows a schematic detail view of the vacuum connection according to the invention with closed embossing chamber and with closed vacuum coupling corresponding to the framed connection to the vacuum generator 100 from FIG. 2, and FIG. 3b the vacuum connection according to the invention with open vacuum coupling.

According to the invention, at least a part of the chamber wall consists of a deformable section, which allows a relative movement of the embossing head in the embossing direction to the carrier. Schematically this is shown in Fig. 2.

In the embodiment according to FIG. 2 a, the deformable section consists of the outer annular wall 15 and a deformable rubber diaphragm 20, which functions as a movable and sealed connection between embossing head 4 and annular wall 15. This sealing ring or membrane 20 seals the outer ring wall 15 from the embossing head 4 out, so that a relative movement between the embossing head 4 and sealingly seated on the support 1 outer annular wall 15 and thus between the carrier 1 and the embossing head 4 is made possible for the embossing ; the movable embossing head 4 thus simultaneously forms part of the pressure chamber wall or the chamber lid. The annular wall 15 sits on the sealing surface 11 with the O-ring 12 on the carrier 1.

In the embodiment of FIG. 2b is instead of the rubber membrane 20 (Fig. 2a) between an outwardly projecting flange 22 of the embossing head 4 and the annular wall 15 in the axial direction yielding tubular element, such as in the form of a bellows 21 or resilient material such , As rubber provided.

When closing the pressure chamber, the outer ring wall 15 is anticipatory, ie it sets first on the carrier 1, while the embossing head 4 until completion of the vacuum generation in an upper position with sufficient distance from the carrier 1 or substrate 2 remains because the carrier 1 remains rigidly positioned with the overlying substrate 2 in the overall system, not shown, and with respect to the drive, not shown, for the lifting axles 6 in the axial direction Z. This advance can z. B. by a (not shown) adjustable stop for determining the Maximalauslenkung between the embossing head 4 and the annular wall 15 in the axial direction Z are minimized in a simple manner.

After closing the pressure chamber and adjusting the working pressure in the chamber, the embossing step takes place, in which the embossing head 4 approaches the stamp 3 for embossing the structure in the substrate 2 to this substrate. Since the embossing head 4 at the same time forms the chamber lid, 7 sliding bushings are no longer required for the Hubachsen 6 and possibly provided supply lines.

Alternatively, the lateral portion can be realized without the outer ring wall 15, such as by the membrane 20 directly between embossing head 4 and carrier 1 z. B. is formed aufsetzend on the carrier 1.

After closing the pressure chamber and before the actual embossing stroke of the embossing head 4 is preferably for further approach to the substrate 2 in

Stamping direction moves, but without touching the substrate 2. This will do that

Chamber volume further reduced and with the channel 101 to 105 closed

Increases pressure in the embossing chamber, so that the pumping process after opening the valve 101 to 105, preferably provided in the connection portion 105, accelerated valve and thus the cycle time is reduced.

This is in contrast to the prior art according to FIG. 1, in which the chamber volume of the embossing chamber remains practically constant during movement of the embossing head.

Another aspect of the present invention relates to the vacuum coupling, which is shown in more detail in Fig. 3a and 3b. For bonding the height-displaceable in the stamping direction (z-direction) vacuum region or the vacuum chamber to the vacuum generating system or the vacuum pump 100, In this embodiment, a vacuum coupling is used in the connecting vacuum channel or pressure channel 101 to 105.

According to FIG. 3, an adapter 101 is mounted as part of the channel 101 to 105 fixed to the outer ring wall 15 and chamber wall. The downwardly facing connection opening of the adapter 101 forms the coupling point 102 of the channel 101 to 105, in which an O-ring 107 is provided for sealing. This connection opening of the adapter 101 is completely sealed on a spring-loaded contact head 103, 106 during the entire production phase, which comprises a plurality of embossing cycles. For this purpose, the adapter 101 and the contact head 103 are movable in the z-direction, wherein the contact at the coupling point 102 remains closed. The contact head 103 is connected to the fixed connection portion 105, which leads to a pressure reservoir or a pump 100, via a flexible, dense bellows 104, z. As rubber or metal, connected. The contact head 103 is slidably positioned by guides 106b and compression springs 106a in the axial direction. The guides 106b allow a displacement of the contact head exclusively in the z-direction, and the compression springs 106a cause a contact pressure at the coupling point 102 during the movement to the chamber opening. This movement of the contact head 103 can be supported by a motor drive, not shown, a pneumatic cylinder or a hydraulic cylinder.

For further indexing of the turntable, the embossing head 4 together with the embossing chamber must be moved out of the engagement area after each embossing cycle. The coupling point 102 remains closed while the embossing chamber is opened at the sealing surface 11.

To change the stamper 3 or for maintenance, the embossing head 4 is moved after opening on the sealing surface 11 in the upper position at a greater distance from the carrier 1, wherein according to FIG. 3b, the vacuum connection is automatically released at the coupling point 102. Thereafter, the unit together with the embossing head to z. B. be pivoted 90 °.

Claims

claims

A device for embossing structures into a substrate (2) in a sealed chamber (10), comprising (a) a support (1) for receiving the substrate (2) and

(B) an embossing head (4) which is movable in the stamping direction relative to the carrier (1), characterized by

(c) a deformable seal (20; 21) between the carrier (1) and the embossing head (4).

2. Device according to claim 1 with a lifting device for moving the embossing head (4) in embossing direction to the carrier (1) after adjustment of the working pressure in the chamber.

3. Apparatus according to claim 1 or 2, wherein the deformable seal (20) directly on the carrier (1) is sealingly placed.

4. Apparatus according to claim 1 or 2, wherein between the deformable seal (20) and the carrier (1) an outer wall of the chamber, preferably in the form of a cylindrical annular wall (15), is provided.

5. Device according to claim 1, 2, 3 or 4, wherein the outer wall or the annular wall (15) or the deformable seal (20), preferably via an O-ring (12), on a sealing surface (11) of the carrier ( 1) is sealingly placed.

6. The device of claim 1, 2, 3, 4 or 5, wherein the deformable seal (20) consists of a resilient material or a rubber ring or a tubular bellows (21).

7. Device according to one of claims 1 to 6, with a working pressure generating means (100) for generating a working pressure in the closed chamber (10).

8. Device according to one of claims 1 to 7, with at least one supply connection (7) on the embossing head (4) for the supply or removal of media in the chamber or out of this chamber, preferably for sucking the punch (3) to the Embossing head (4).

9. Device according to one of claims 1 to 8, comprising means for introducing a moldable substrate (2) on the carrier (1).

10. Device according to one of claims 1 to 9, wherein a punch (3), preferably by negative pressure, is held on the embossing head (4).

A method of embossing structures into a substrate (2) in a sealed chamber (10) using an apparatus according to any one of claims 1 to 10, comprising the following steps, in this order: a) closing the chamber, b) generating c) moving the embossing head in embossing direction relative to the support for forming the substrate (2) arranged on the support (1), d) venting the chamber and e) removing the im Step c) embossed substrate.

12. The method of claim 11, wherein between step a) and step c) of the embossing head (4) is lowered in order to approach the substrate to be embossed (2) without touching.

13. The method of claim 12, wherein the lowering of the embossing head (4) takes place at least partially during the step b).

14. The method according to any one of claims 11 to 13, wherein in step b) in the closed chamber (10), a vacuum, a negative pressure or an overpressure is generated.

15. The method according to any one of claims 11 to 14, wherein prior to step a) a moldable substrate (2), preferably a prefabricated substrate blank, introduced into the chamber (10) and preferably deposited on the carrier (1).

16. Pressure chamber arrangement having a working pressure generating device (100) and a pressure chamber (10) which can be separated relative to this and a pressure channel (101 to 105) which can be separated at a self-sealing coupling point (102) and which has an adapter section (10) adjoining the pressure chamber (10). 101) and a connection section (105) adjoining the working pressure generating device (100), and a spring-loaded contact head (103, 106) disposed between a free end of the adapter section (101) facing away from the pressure chamber (10) and one of the working pressure generating device (100 ) facing away from the terminal portion (105) is arranged sealingly.

17. Arrangement according to claim 16, wherein the contact head (103) via a flexible, gas-tight connection (104) with the connection portion (105) and / or the adapter portion (101) is connected.

18. Arrangement according to claim 17, wherein the flexible, gas-tight connection (104) has a bellows, preferably made of rubber or metal.

19. Arrangement according to claim 16, 17 or 18, wherein the contact head (103) by means of a guide device (106), which preferably at least one spring (106 a) and at least one guide rail (106 b), guided during a working stroke and against the adapter portion ( 101) or sealingly pressed against the terminal portion (105).

20. Arrangement according to one of claims 16 to 19, wherein the coupling point (102) by an O-ring (107) is sealed.

21. Device according to one of claims 1 to 10 in combination with an arrangement according to one of claims 16 to 20.