WO2016005965A1

WO2016005965A1 - Improved systems and methods for computerized direct writing

Info

Publication number: WO2016005965A1
Application number: PCT/IL2015/000032
Authority: WO
Inventors: Uri Gold; Ram Oron
Original assignee: Orbotech Ltd.
Priority date: 2014-07-08
Filing date: 2015-06-23
Publication date: 2016-01-14
Also published as: KR102330565B1; TWI660856B; KR20170030486A; TW201617233A; CN106574901B; CN106574901A

Abstract

A method for computerized direct optical writing on a patterned substrate including the steps of providing a printing instruction database containing precise instructions for printing on the patterned substrate, imaging the patterned substrate to provide a patterned substrate image, and employing a computer referencing at least the printing instruction database and the patterned substrate image for instructing an optical writer to write on the patterned substrate in accordance with the precise instructions without carrying out fiducial registration between the printing instruction database and the patterned substrate during the time between the imaging and the instructing.

Description

IMPROVED SYSTEMS AND METHODS FOR COMPUTERIZED DIRECT WRITING

FIELD OF THE INVENTION [0001] The present invention relates to computerized direct writing generally.

BACKGROUND OF THE INVENTION

[0002] Various approaches to computerized direct writing are known in the art. The present invention seeks to provide improved systems and methods for computerized direct writing. For example, US patent 7,508,515 incorporated herein by reference in its entirety is described a state of the art approach.

SUMMARY OF THE INVENTION [0003] The present invention seeks to provide an improved system and method for computerized direct writing.

[0004] An advantage of the system and method according to the invention is that it can produce improved printing accuracy over fiducial registration based methods as it can provide better accuracy per each element or group of elements, and the printing method can compensate for global and local distortions of the substrate.

[0005] There is thus provided in accordance with a preferred embodiment of the present invention a method for computerized direct optical writing on a patterned substrate including the steps of providing a printing instruction database containing precise instructions for printing on the patterned substrate, imaging the patterned substrate to provide a patterned substrate image, and employing a computer for referencing at least the printing instruction database and the patterned substrate image for instructing an optical writer to write on the patterned substrate in accordance with the precise instructions without carrying out fiducial registration between the printing instruction database and the patterned substrate during the time between the imaging and the instructing.

[0006] Preferably, referencing at least the printing instruction database and the patterned substrate image for instructing an optical writer to write on the patterned substrate in accordance with the precise instructions also includes providing CAM data corresponding to the patterned substrate, computerized mutual overlaying of an imaged pattern of the patterned substrate and the CAM data corresponding to the patterned substrate, and utilizing information from the overlaying in providing the precise instructions.

[0007] Preferably, utilizing information from the overlaying in providing the precise instructions includes utilizing the CAM data to modify the precise instructions contained in the printing instruction database. Additionally, the printing instruction database is used to modify the CAM data for use in the utilizing step.

[0008] Preferably, the imaging is executed by an automated optical inspection subsystem. Preferably, the optical writer is a direct imaging subsystem.

[0009] There is also provided in accordance with another preferred embodiment of the present invention a system for computerized direct optical writing on a patterned substrate including a printing instruction database containing precise instructions for printing on the patterned substrate, imaging functionality operable for imaging the patterned substrate to provide a patterned substrate image, and a computer operable for referencing at least the printing instruction database and the patterned substrate image and for instructing an optical writer to write on the patterned substrate in accordance with the precise instructions without carrying out fiducial registration between the printing instruction database and the patterned substrate during the time between the imaging and the instructing.

[0010] Preferably, the computer is also operable for mutual overlaying of an imaged pattern of the patterned substrate and CAM data corresponding to the patterned substrate, and for utilizing information from the overlaying in providing the precise instructions.

[0011] Preferably, the computer is also operable for employing the CAM data to modify the precise instructions contained in the printing instruction database. Additionally, the printing instruction database is used to modify the CAM data for use by the computer.

[0012] Preferably, the imaging functionality is encapsulated in an automated optical inspection subsystem. Preferably, the optical writer is a direct imaging subsystem.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be understood and appreciated more fully from the following detailed description taken with the drawings in which:

[0014] Fig. 1A is a simplified illustration of a system for computerized direct writing constructed and operative in accordance with one preferred embodiment of the present invention;

[0015] Fig. IB is a simplified illustration of a system for computerized direct writing constructed and operative in accordance with another preferred embodiment of the present invention;

[0016] Fig. 2 is a simplified flow chart illustrating steps in the operation of the systems of Figs. 1A and IB;

[0017] Fig. 3 is a simplified flow chart illustrating optional additional steps in the operation of the systems of Figs. 1 A - 2;

[0018] Fig. 4A is a simplified block diagram illustration of one embodiment of part of the systems of Figs. lA - 3; and

Fig. 4B is a simplified block diagram illustration of another embodiment of part of the systems of Figs. 1A - 3.

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DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0019] Reference is now made to Fig. 1 A, which is a simplified illustration of a system for computerized direct writing constructed and operative in accordance with one preferred embodiment of the present invention.

[0020] As seen in Fig. 1A, the system preferably comprises a chassis 101 which is preferably mounted on a conventional optical table 102. Chassis 101 defines a substrate support surface 104 onto which a patterned substrate 106 may be placed. Substrate 106 may be, for example, a circuit board onto which a solder mask is to be printed.

[0021] A bridge 112 is arranged for linear motion relative to substrate support surface

104 along a first axis 114, defined with respect to chassis 101. A read/write assembly 116 is arranged for linear motion relative to bridge 112 along a second axis 118, perpendicular to first axis 114.

[0022] The system preferably also includes a control assembly 124, preferably including a computer 126 having a user interface 128. Computer 126 preferably includes software modules operative to operate read/write assembly 116.

[0023] Control assembly 124 also preferably includes a printing instruction database

130 containing precise instructions for printing on patterned substrate 106.

[0024] In accordance with a preferred embodiment of the present invention, read/write assembly 116 preferably includes an automated optical inspection subsystem (AOI) 132 operable for imaging patterned substrate 106 to provide a patterned substrate image 134 of patterned substrate 106 to computer 126, and a direct imaging subsystem (DI) 136 including an optical writer operable for writing on patterned substrate 106.

[0025] It is a particular feature of this embodiment of the present invention that computer 126 is operable for referencing precise printing instructions stored in printing instruction database 130 and patterned substrate image 134, and for providing precise printing instructions 138 to DI 136 for writing on patterned substrate 106 without carrying out fiducial registration between the printing instruction database and patterned substrate 106 during the time between imaging patterned substrate 106 by AOI 132 and writing on patterned substrate 106 by DI 136.

[0026] Reference is now made to Fig. IB, which is a simplified illustration of a system for computerized direct writing constructed and operative in accordance with another preferred embodiment of the present invention. [0027] As seen in Fig. IB, the system preferably comprises a motion chassis 201 which is preferably mounted on a lower stationary chassis 202 and is arranged for linear motion along an axis 203 defined with respect to lower stationary chassis 202. Chassis 201 defines a substrate support surface 204 onto which a patterned substrate 206 may be placed. Substrate 206 may be, for example, a circuit board onto which a solder mask is to be printed.

[0028] A stationary bridge 212 is preferably supported above motion chassis 201 and allows for linear movement of motion chassis 201 therebelow along axis 203.

[0029] The system preferably also includes a control assembly 224, preferably including a computer 226 and a printing instruction database 230 containing precise instructions for printing on patterned substrate 206.

[0030] In accordance with a preferred embodiment of the present invention, bridge 212 preferably supports an automated optical inspection subsystem (AOI) 232 operable for imaging patterned substrate 206 to provide a patterned substrate image 234 of patterned substrate 206 to computer 226, and a direct imaging subsystem (DI) 236 including an optical writer operable for writing on patterned substrate 206.

[0031] It is a particular feature of this embodiment of the present invention that computer 226 is operable for referencing precise printing instructions stored in printing instruction database 230 and patterned substrate image 234, and for providing precise printing instructions 238 to DI 236 for writing on patterned substrate 206 without carrying out fiducial registration between the printing instruction database and patterned substrate 206 during the time between imaging patterned substrate 206 by AOI 232 and writing on patterned substrate 206 by DI 236.

[0032] Although the system of Fig. IB provides for one dimensional movement of motion chassis 201 relative to stationary chassis 202, it is appreciated that a system which provides for two-dimensional movement of motion chassis 201 relative to stationary chassis 202 may also be provided.

[0033] Reference is now made to Fig. 2, which is a simplified flow chart illustrating steps in the operation of the systems of Figs. 1A and IB. As shown in Fig. 2, a panel, such as patterned substrates 106 and 206 of Figs. 1A & IB is initially loaded onto the system (250). Thereafter, the panel is preferably scanned (252) and is imaged (254). The acquired image is then preferably processed (256), such processing may include detection and characterization of individual elements or groups of elements. Such characterization may include size, location, shape, and type. A printing instruction database is referenced to provide precise printing instructions which correlate to elements of the acquired image (258). Thereafter, the precise printing instructions are employed to directly write onto the panel (260).

[0034] It is a particular feature of the present invention that the method illustrated in Fig. 2 comprises providing a printing instruction database containing precise instructions for printing on the patterned substrate, imaging the patterned substrate to provide a patterned substrate image, referencing the printing instruction database and the patterned substrate image for instructing an optical writer to write on the patterned substrate in accordance with the precise instructions without carrying out fiducial registration between the printing instruction database and the patterned substrate during the time between the imaging and the instructing.

[0035] Reference is now made to Fig. 3, which is a simplified flow chart illustrating optional additional steps in the operation of the systems of Figs. 1A - 2. Preferably, the referencing of the printing instruction database to provide precise printing instructions as described hereinabove with reference to Figs. 1A - 2 includes providing CAM data corresponding to the patterned substrate and computerized mutual overlaying of the patterned substrate image and the CAM data corresponding to the patterned substrate, and automatically employing information from the overlaying in providing the precise instructions. It is appreciated that the CAM data is preferably stored in the printing instruction database.

[0036] As shown in Fig. 3, the step of providing precise printing instructions which correlate to elements of the acquired image (300) initially includes retrieving CAM data corresponding to the patterned substrate (302) and receiving processed image data of the substrate (304). Thereafter, the CAM data corresponding to the patterned substrate is overlaid onto the patterned substrate image (306) and information resulting from the overlaying is employed in providing the precise instructions (308). It is appreciated that information resulting from the overlaying may include, for example, pattern matching of patterns comprised in the CAM data and patterns appearing in the receiving processed image data of the substrate. As described hereinabove, it is a particular feature of the present invention that providing the precise instructions is performed without carrying out fiducial registration between the system and the patterned substrate during the time between the imaging and providing the precise instructions.

[0037] Reference is now made to Figs. 4A and 4B, which are simplified block diagram illustrations of two alternative embodiments of part of the systems of Figs. 1A - 3. Fig. 4A illustrates a rule-based embodiment and Fig. 4B illustrates a CAM data and rule-based embodiment. The elements illustrated in Figs 4A or in Fig. 4B are instrumental in executing step 258 of Fig. 2 in which a printing instruction database is referenced to provide precise printing instructions which correlate to elements of the acquired image. The elements illustrated in Fig. 4B are instrumental in executing step 308 of Fig. 3, in which information resulting from overlaying CAM data corresponding to the patterned substrate onto the patterned substrate image is employed in providing the precise instructions.

[0038] As shown in Fig. 4A, the system preferably includes a plurality of rules 410 which govern the placement of any overlay component layer 404 over a corresponding base component layer 402. It is appreciated that rules 410 may be stored in a database, such as databases 130 and 230 of Figs. 1A and IB.

[0039] For example, rules 410 may dictate an allowed variation in the placement angle between overlay component layer 404 and corresponding base component layer 402. Rules 410 may also govern mutual alignment of a multiplicity of overlay components in an overlay component layer 404, each of the multiplicity of overlay components corresponding to one of a multiplicity of base components in base component layer 402, the base components having a different mutual alignment. For example, a rule may establish that a frame of a predetermined width is printed around any square shape of size X x Y. Such a shape may correspond to a pad in a printed circuit board. Furthermore a rule may establish that mutually aligned frames of a predetermined width are printed around each one of a predetermined shaped array of square shapes of size X x Y. Such an array may correspond to an array of pads for mounting of a given circuit component on a PCB.

As another example, a rule may establish that all elongate shapes having an aspect ratio greater than R are overprinted with an frame of a thickness of T. This type of rule may be applied, for example, to elongate conductors. [0040] Furthermore, rules 410 may include compliance rules which govern the overlay component layer 404 and corresponding base component layer 402. For example, rules 410 may include rules regarding minimum dimensions of an overlay component of component layer 404 relative to a base component of base component layer 402. It is therefore appreciated that rules 410 are operative to modify the precise placement of overlay component layer 404 over a corresponding base component layer 402.

As shown in Fig. 4B, the CAM data 400 includes a plurality of pairs of design layers, each of the pairs preferably including a base component layer 402 and an overlay component layer 404 to be written onto a corresponding base component layer 402. Base component layer 402 and the overlay component layer 404 may be of different types and may be designated for executing different functions on the resulting circuit board.

[0041] It is appreciated that data encapsulated in CAM data 400 may dictate modification of rules 410. For example, data encapsulated in CAM data 400 may dictate minimum dimensions of an overlay component of component layer 404 relative to a base component of base component layer 402, and may thereby overrule at least one of rules 410. Furthermore, the CAM data may be used for selecting or confirming correct selection of appropriate ones of rules 410.

[0042] An imaging subsystem 420, such as AOI subsystems 132 and 232 of Figs. 1A and Fig. IB is preferably provided for imaging patterned substrates such as patterned substrates 106 and 206 of Figs. 1A and IB. Once a patterned substrate image 422, such as patterned substrate images 134 and 234 of Figs. 1A and IB is acquired, contouring functionality 424 is preferably employed to provide a contoured image 426 of the patterned substrate image. This contouring process is described in U.S. Patent 7,181,059 of the Applicant.

[0043] Image overlapping functionality 428 is preferably provided for overlapping contoured image 426 over base component layer 402, thereby matching existing elements in contoured image 426 to corresponding elements in base component layer 402. Image overlapping functionality 428 may employ well known geometric shape matching processes or methods described in U.S. Patent 7,388,978 of the Applicant.

[0044] Functional tagging functionality 430 is preferably provided for functional tagging of elements of base component layer 402. A method of functional tagging is described in U.S. Patent 7,388,978 of the Applicant.

[0045] Functional tagging of elements of base component layer 402 is then employed in conjunction with corresponding overlay component layer 404 and rules 410 to provide an image design 432. Image design is thereafter provided to a direct imaging subsystem 440 operable for writing on the patterned substrate.

[0046] It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove as well as modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not in the prior art.

Claims

C L A I M S

1. A method for computerized direct optical writing on a patterned substrate comprising the steps of:

providing a printing instruction database containing precise instructions for printing on said patterned substrate;

imaging said patterned substrate to provide a patterned substrate image; and employing a computer for referencing at least said printing instruction database and said patterned substrate image for instructing an optical writer to write on said patterned substrate in accordance with said precise instructions without carrying out fiducial registration between said printing instruction database and said patterned substrate during the time between said imaging and said instructing.

2. A method for direct writing on a patterned substrate according to claim 1 and wherein said referencing at least said printing instruction database and said patterned substrate image for instructing an optical writer to write on said patterned substrate in accordance with said precise instructions comprises:

providing CAM data corresponding to said patterned substrate;

computerized mutual overlaying of an imaged pattern of said patterned substrate and said CAM data corresponding to said patterned substrate; and

utilizing information from said overlaying in providing said precise instructions.

3. A method for direct writing on a patterned substrate according to claim 2 and wherein said utilizing information from said overlaying in providing said precise instructions comprises utilizing said CAM data to modify said precise instructions contained in said printing instruction database.

4. A method for direct writing on a patterned substrate according to claim 2 and wherein said printing instruction database is used to modify said CAM data for use in said utilizing step.

5. A method for direct writing on a patterned substrate according to claim 1 and wherein said imaging is executed by an automated optical inspection subsystem.

6. A method for direct writing on a patterned substrate according to claim 1 and wherein said optical writer is a direct imaging subsystem.

7. A system for computerized direct optical writing on a patterned substrate comprising:

a printing instruction database containing precise instructions for printing on said patterned substrate;

imaging functionality operable for imaging said patterned substrate to provide a patterned substrate image; and

a computer operable for referencing at least said printing instruction database and said patterned substrate image and for instructing an optical writer to write on said patterned substrate in accordance with said precise instructions without Carrying out fiducial registration between said printing instruction database and said patterned substrate during the time between said imaging and said instructing.

8. A system for direct writing on a patterned substrate according to claim 7 and also and wherein said computer is also operable for mutual overlaying of an imaged pattern of said patterned substrate and CAM data corresponding to said patterned substrate, and for utilizing information from said overlaying in providing said precise instructions.

9. A system for direct writing on a patterned substrate according to claim 8 and wherein said computer is also operable for employing said CAM data to modify said precise instructions contained in said printing instruction database.

10. A system for direct writing on a patterned substrate according to claim 8 and wherein said printing instruction database is used to modify said CAM data for use by said computer.

11. A system for direct writing on a patterned substrate according to claim 7 and wherein said imaging functionality is encapsulated in an automated optical inspection subsystem.

12. A system for direct writing on a patterned substrate according to claim 7 and wherein said optical writer is a direct imaging subsystem.