JP3090107B2 - Photomask drawing apparatus and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for forming a photomask, and more particularly, to a CAD (computer aided design).
The present invention relates to a photomask drawing apparatus and method for drawing (drawing) a photomask of a printed wiring board or the like from CAD data (drawing data) of a printed wiring board or the like designed using the above method.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing an example of the configuration of a conventional photomask drawing apparatus.

The conventional photomask drawing apparatus shown in FIG. 4 includes a data input unit 11 for inputting drawing data, a data processing unit 14 for converting drawing data, and a data processing unit 14.
The image data is corrected by a drawing data scale correction unit 13 for performing a format conversion while multiplying and correcting the data input to the unit, a drawing machine unit 16 for drawing a photomask for a printed wiring board, and a drawing data scale correction unit 13. And a drawing machine control unit 15 that controls the drawing machine unit 16 based on the input data.

In a conventional photomask drawing apparatus,
For example, before starting drawing, a drawing device (drawing machine 1
A predetermined scale value (for example, x 1.0004) according to a change in the surrounding environment where 6) is installed is determined by an operator.
The input data such as a keyboard (not shown) provided in the drawing data scale correction unit 13 is registered in a storage device such as a memory provided inside the correction unit 13.

Thus, the drawing data input from the data input unit 11 is supplied to the drawing data scale correction unit 13 via the data processing unit 14, and the drawing data scale correction unit 13 assigns a scale value to the drawing data. The image data is converted into a format that can be easily received by the image forming machine control unit 15 and corrected by the data processing unit 14.
Is supplied to the drawing machine control unit 15 via the. Then, the drawing machine controller 16 is controlled by the drawing machine controller 15, and a photomask of an arbitrary scale is drawn.

[0006]

However, in the above-described conventional photomask apparatus, the environment in the process in which the photomask is actually used is taken into consideration with respect to the environment in the process in which the photomask is formed. Therefore, even when accurate photometric accuracy is maintained when a photomask is drawn using CAD or the like, the photomask expands and contracts in an environment in the process of actually using the photomask described above. There was a problem that it would.

In a conventional photomask drawing apparatus,
Input of a predetermined scale value to the photomask drawing device according to a change in the surrounding environment where the drawing device is installed is performed by an operator (manually) using input means such as a keyboard, and therefore, an input error occurs. In this case, there is a problem (defect) that a photomask is created with wrong dimensions due to wrong scale values.

Accordingly, an object of the present invention has been made in view of the above problems, and takes into consideration the temperature and humidity difference between the environment in which a photomask is drawn and the environment in which the photomask is actually used. It is an object of the present invention to provide a photomask drawing apparatus capable of achieving optimum dimensional accuracy in a process in which a photomask is used by determining a scale value.

A further object of the present invention is to provide a photomask drawing apparatus capable of automatically setting a scale value at the time of drawing a photomask, thereby eliminating input errors caused by manual operation and improving reliability. To provide.

[0010]

In order to achieve the above object, the present invention provides a data input unit for reading drawing data of a printed wiring board, and a data input unit for reading data of a drawing room and a photomask formed in the manufacturing process. A parameter storage unit that stores various parameters such as humidity, and the parameters are read from the parameter storage unit, and a temperature-humidity difference obtained from the temperature-humidity of each manufacturing process in which the drawing room and the created photomask are used, A scale factor calculation unit that calculates an optimal scale factor, a data scale correction unit that multiplies the drawing data by the scale factor calculated by the scale factor calculation unit, and a drawing data processed by the data scale correction unit. A drawing machine control unit for outputting a control signal for drawing the photomask, Is characterized in being configured with a drawing machine unit for drawing a photomask, a based on the control signal outputted from the control unit.

Further, the present invention provides a step of reading drawing data of a printed wiring board and a step of storing various parameters such as temperature and humidity in a drawing room and each manufacturing step in which a drawn photomask is used in a storage means. Reading the stored parameters, and calculating an optimal scale factor by a temperature and humidity difference obtained from the temperature and humidity of each manufacturing process in which the drawing room and the drawn photomask are used; and Multiplying the drawing data by a scale factor; outputting a control signal for drawing the photomask based on the drawing data multiplied by the scale factor; and drawing a photomask based on the control signal. , Are provided.

[0012] According to the invention described above, the scale factor calculating section includes the attribute information specifying the manufacturing process included in the photomask data registered in the data input section, and the temperature of the drawing room registered in the parameter storage section. The scale factor at the time of drawing is calculated and registered from the humidity, the temperature and humidity of each manufacturing process, and the expansion and contraction coefficient with respect to the temperature and humidity of the film used for the photomask. Further, the drawing data scale correction unit registers the calculated scale factor by multiplying it by the photomask data. The data processing unit converts the photomask data multiplied by the scale factor into a format that can be easily received by the drawing machine control unit, and delivers the format to the drawing machine control unit. Finally, the drawing machine draws the photomask data that has been format-converted on the film under the control of the drawing machine or the control unit. Thus, the photomass according to the present invention can always maintain the optimal dimensional accuracy in each step in which the photomask is used.

[0013]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a photomask drawing apparatus according to the present invention.

The photomask drawing apparatus of the present invention shown in FIG. 1, which performs processing with the aid of a computer, comprises a data input unit 1 including a medium reader, a CRT display, a keyboard and a mouse, and a digital computer. Scale factor calculation unit 2, drawing data scale correction unit 3, data processing unit 4, drawing machine control unit 5 composed of digital computer, online line, etc.
And a drawing machine 6 composed of a laser transmitting device, a film holding mechanism, and the like.

A data input unit 1 reads and stores drawing data of a printed wiring board including attribute information indicating a manufacturing process, and a scale factor calculation unit 2 stores a temperature / humidity expansion / contraction coefficient of a photomask material. The temperature and humidity of the drawing room and the printed wiring board manufacturing process stored in the parameter storage unit 7 are extracted from the attribute information indicating the manufacturing process, and the optimum scale factor at the time of drawing is calculated. The data scale correction unit 3 includes a scale factor data input unit 1 calculated by the scale factor calculation unit 2.
Is registered by multiplying the drawing data registered in.

The data processing unit 4 converts the drawing data registered in the drawing data scale correction unit 3 into a format that the drawing machine control unit 5 can easily receive.
The drawing machine control unit 5 controls a drawing machine for drawing the drawing data converted in format by the data processing unit 4 on a film of a photomask material, and the drawing machine unit 6 converts the drawing data in the data processing unit 4. The created drawing data is actually drawn on a film of a photomask material based on an instruction from the drawing machine control unit 5.

Further, the data input unit 1 reads the drawing data for the photomask for each step required for manufacturing the printed wiring board. The drawing data created by CAD or the like has attribute information that specifies a printed wiring board manufacturing process. The scale factor calculation unit 2 reads the temperature and humidity of the process indicated by the attribute information of the drawing data stored in the parameter storage unit 7 and the temperature and humidity of the drawing room, and obtains the temperature and humidity difference between the drawing room and the printed wiring board manufacturing process. , Multiply the temperature / humidity expansion / contraction coefficient of the polyester film of the photomask material registered in advance, calculate the amount of dimensional expansion / contraction due to the temperature / humidity difference, and calculate the scale factor to maintain the optimal dimensional accuracy in the printed wiring board manufacturing process I do.

The drawing data scale correction unit 3 multiplies the scale data calculated by the scale factor calculation unit 2 with the drawing data and registers the data. The data processing unit 4 converts the drawing data into a format that can be easily received by the drawing machine. The drawing machine control unit 5 performs switching control such as handling of a film of a photomask material and laser oscillation, and the drawing machine unit 6 actually forms a photomask on the film.

Next, the operation of the present invention configured as described above will be described with reference to FIGS.
FIG. 2 is a flowchart for explaining the operation of the embodiment of the present invention.

As shown in FIG. 2, the photomask drawing apparatus of the present invention first inputs various drawing data necessary for manufacturing a printed wiring board (step 21) and adds (adds) the drawing data (CAD data) to the drawing data (CAD data). The read attribute information is read (step 22). The attribute information is process identification information attached in order to clarify in which step of the printed wiring board manufacturing process a photomask drawn based on the drawing data is used. It is read and stored in the parameter storage unit 7.

Next, from the parameter file in the parameter storage unit 7, the temperature and humidity of the drawing room in which the photomask drawing apparatus of the present invention is installed, and the attribute information added to the drawing data in the printed wiring board manufacturing process. The temperature and humidity are read (step 23), the temperature difference and the humidity difference between the drawing room and the printed wiring board manufacturing process indicated by the attribute information are obtained, and the film expansion amount is calculated by multiplying the temperature and humidity expansion coefficient registered in advance. Determine the scale factor at the time of drawing (step 2
4).

Next, the drawing data is multiplied by the scale factor (step 25), and the drawing data multiplied by the scale factor is converted into a format that can be easily received by the drawing machine control unit 5 and output (step 26).

Finally, the drawing machine control unit 5 controls the handling of the film of the photomask material and performs switching control such as laser oscillation, and based on the drawing data, the drawing machine unit 6 places the photomask on the film. The image is drawn, and a series of steps ends (step 27).

Next, the above operation will be described in more detail with reference to specific examples (using actual data and the like).

First, from a drawing data input unit 1, a photomask for a photomask using five items of a product name, a version number, a total number of layers, a layer surface, and attribute information for identifying a manufacturing process as a key. The drawing data is registered (step 21). Then, attribute information (for example, "DE" indicating a circuit forming process, "DS" indicating a solder resist process, etc.) for identifying a manufacturing process of the drawing data registered in step 21 is read (step 22).

Next, the temperature and humidity of each step of manufacturing a printed wiring board requiring a photomask are individually monitored by sensors and stored in a memory in real time.
Of the printed wiring board manufacturing process (for example, the temperature of the circuit forming process = 25) indicated by the attribute information for manufacturing process identification added to the drawing data from the parameter storage unit 7
° C, humidity = 60% RH) and the temperature and humidity of the drawing room in which the photomask drawing device is installed (for example, temperature = 22.5
(° C., humidity = 53% RH) is read (step 23).

Then, a temperature / humidity difference is calculated from the temperature / humidity of the printed wiring board manufacturing process and the temperature / humidity of the drawing room read in step 23, and a polyester base, which is a photomask material registered in advance, is used as a support. And the expansion and contraction coefficient (1.79 × 10 ⁻⁵ cm / cm / cm, respectively) of a film using a silver halide (AgCl or the like) as a photosensitive material with respect to temperature and humidity.
(1.0 ° C., 1.03 × 10 ⁻⁵ cm / cm /% RH) to calculate the dimensional expansion / contraction of the photomask film due to the temperature and humidity difference between the printed wiring board manufacturing process and the drawing room, and use the photomask. A scale factor for maintaining an optimal dimensional value in the printed wiring board manufacturing process is calculated (Step 24).

An example of a specific calculation method will be described below. That is, in the circuit forming process, when it is assumed that the dimensional accuracy of the photomask is required to be a theoretical value, Xcm subjected to seasoning (environmental adaptation) in the drawing room (temperature = 22.5 ° C., humidity = 53% RH). In the circuit formation process, the base film is affected by the temperature difference.

[0030]

[Equation 1] (Temperature of circuit forming process−Temperature of drawing room) × 1.79
× 10 ⁻⁵ (cm / cm / ° C.) × X (cm) ··· Expands by (formula 1). Therefore, in the case of the above conditions,

[0031]

[Equation 2] (25 ° C.-22.5 ° C.) × 1.79 × ^-5 (cm / cm / ° C.) × X (cm) = 4.475 × 10 ^-5 × X (cm) Become. Also, under the influence of humidity difference

[0032]

[Expression 3] (Humidity of circuit forming process−Humidity of drawing room) × 1.03 × 10 ⁻⁵ (cm / cm /% RH) × X (cm) (Expression 3) Therefore, in the case of the above conditions,

[0033]

(60% RH-53% RH) × 1.03 × 10 ⁻⁵ (cm / cm /% RH) × X (cm) = 7.21 × 10 ⁻⁵ × X (cm) (Equation 4) Will only grow.

Therefore, assuming that a photomask is created as it is with the image data created based on the theoretical values, in the circuit forming process,

[0035]

(Expression 5) 4.475 × 10−5 × X (cm) + 7.21 × 10 ⁻⁵ × X (cm) = 11.685 × 10 ⁻⁵ × X (cm) (Equation 5) Therefore, in order to maintain the theoretical value in the circuit forming process, it is necessary to

[0036]

X (cm) / (X + 11.685 × 10 ⁻⁵ × X (cm) = 0.99988 (times) It is necessary to multiply by the scale factor of (Equation 6).

The scale factor calculated in this way is multiplied by the original image data for the photomask used in the circuit forming step (step 25).

Next, in step 25, the drawing data multiplied by the optimum scale factor is converted by the data processing unit 4 shown in FIG. 1 into a format which is also easily received by the drawing machine control unit 5 in FIG. And the drawing machine control unit 5
(Step 26).

Thereafter, in the drawing machine section 6 shown in FIG. 1, setting of the film set in the photomask drawing apparatus to the drawing table, switching of the argon ion laser as the drawing light source, movement of the drawing light source, and the like are performed. A predetermined pattern is drawn based on the drawing data controlled and multiplied by the scale factor supplied by the drawing machine controller 5 (step 27).

By the way, since the printer used in the circuit forming process uses an ultra-high pressure mercury lamp, the temperature of the photomask surface slightly increases during exposure.

Next, a scale factor is calculated for the temperature and humidity of the drawing room and the temperature and humidity of each manufacturing process, taking into account the temperature rise caused by the manufacturing equipment, which is used when actually manufacturing using a photomask. Next, a photomask drawing apparatus for drawing a photomask will be described.

FIG. 3 is a diagram showing various parameters stored in the parameter storage unit 7.

As shown in FIG. 3, the parameter storage unit 7 stores (updates) the temperature and humidity of the drawing room and the temperature and humidity of each manufacturing process in real time as described above. In the parameter storage unit 7, a temperature rise 7a caused by a manufacturing facility to be used when manufacturing is actually performed using a photomask is stored.

For example, a printer used in a circuit forming process uses an ultra-high pressure mercury lamp.
The surface of the photomask rises to 28 ° C. Therefore, the temperature and humidity of the drawing room (for example, temperature = 22.5 ° C., humidity = 53% R
H), temperature and humidity (for example, temperature = 25 ° C.,
Humidity = 60% RH), the film stretch amount is

[0045]

[Expression 7] {(28 ° C.-22.5 ° C.) × 1.79 × 10 ⁻⁵ (cm / cm / ° C.) + (60% RH−53% RH) 1.03 × 10 ⁻⁵ (cm / cm /% RH)} × Xcm = 17.055 × 10 ⁻⁵ × X (cm) (Equation 7)

[0046]

X (cm) / (X + 17.055 × 10 ⁻⁵ × X) (cm) = 0.99983 (Expression 8) As described above, by calculating the scale factor by adding the temperature rise 7a as a new parameter, it is possible to calculate a more accurate scale factor.

Then, by using the scale factor calculated by this (Equation 8) and executing the steps after step 25 in FIG. 2, it is possible to draw a photomask having a more accurate and optimum dimensional accuracy. It is possible to provide a photomask drawing apparatus.

[0048]

As described above, according to the present invention, not only the temperature and humidity at the place where the photomask is drawn, but also
The scale factor at the time of drawing is determined in consideration of the temperature and humidity of the manufacturing process that actually uses the photomask, and the scale factor calculation and the expansion of the scale factor into the drawing data are automated, so that the printing using the photomask is performed. In the wiring board manufacturing process, optimal dimensional accuracy can be maintained, and the manufacturing yield of printed wiring boards can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a photomask drawing apparatus of the present invention.

FIG. 2 is a flowchart for explaining the operation of the embodiment of the present invention.

FIG. 3 is a diagram showing various parameters stored in a parameter storage unit.

FIG. 4 is a block diagram showing an example of a configuration of a conventional photomask drawing apparatus.

[Explanation of symbols]

 1 data input unit 2 scale factor calculation unit 3 drawing data scale correction unit 4 data processing unit 5 drawing machine control unit 6 drawing machine unit 7 parameter storage unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03F 1/08-1/16

Claims (14)

(57) [Claims] 1. A data input unit for reading drawing data, a parameter storage unit for storing various parameters such as environment information of each of manufacturing steps in which a drawing room and a drawn photomask are used, and a parameter storage unit. Reading the parameters,
A scale factor calculation unit that calculates an optimum scale factor based on a difference between environments in the respective manufacturing processes in which the drawing room and the drawn photomask are used; and a scale factor calculated by the scale factor calculation unit. A data scale correction unit that performs a predetermined calculation process on the drawing data based on the drawing data, and outputs a control signal for drawing the photomask based on the drawing data calculated by the data scale correction unit. A photomask drawing apparatus, comprising: a drawing machine control unit; and a drawing machine unit that draws a photomask based on a control signal output from the drawing machine control unit. 2. A data input unit for reading drawing data of a printed wiring board; a parameter storage unit for storing various parameters such as temperature and humidity in each of manufacturing steps in which a drawing room and a drawn photomask are used; Reading the parameter from the parameter storage unit,
A scale factor calculator for calculating an optimum scale factor based on a temperature / humidity difference obtained from the temperature / humidity of each manufacturing process in which the drawing room and the drawn photomask are used; and a scale calculated by the scale factor calculator. A data scale correction unit that multiplies the drawing data by a factor; a drawing machine control unit that outputs a control signal for drawing the photomask based on the drawing data processed by the data scale correction unit; And a drawing machine unit for drawing a photomask based on a control signal output from the drawing machine control unit. 3. The manufacturing method according to claim 1, wherein the scale factor calculation unit is further configured to perform temperature-humidity difference information obtained from the temperature-humidity of each of the manufacturing steps in which the drawing room and the drawn photomask are used, and further perform manufacturing using the photomask. 3. The photomask drawing apparatus according to claim 2, wherein a further optimum scale factor is calculated by adding information on a temperature rise caused by the manufacturing equipment used in the process. 4. The photomask drawing apparatus according to claim 2, wherein the parameter storage unit can individually recognize and store the temperature and humidity for each manufacturing process. 5. The photomask drawing apparatus according to claim 1, wherein said scale factor calculation unit has a coefficient of expansion and contraction of the photomask material with respect to temperature and humidity. 6. The photomask according to claim 1, wherein said drawing data includes attribute information specifying a manufacturing process in which the drawn photomask is used. Drawing device. 7. The photomask drawing apparatus according to claim 1, wherein said drawing data is CAD data. 8. A step of reading drawing data, a step of storing various parameters such as environmental information of each of manufacturing steps in which the drawing room and the drawn photomask are used in a storage means, and a step of reading the stored parameters. Reading, based on the environment difference of each manufacturing process in which the drawing room and the drawn photomask are used, a step of calculating an optimal scale factor, based on the calculated scale factor, based on the drawing data, Performing a predetermined arithmetic process, outputting a control signal for creating the photomask based on the image data subjected to the arithmetic process, and creating a photomask based on the control signal. A method for creating a photomask, comprising: 9. A step of reading drawing data of a printed wiring board; a step of storing various parameters such as temperature and humidity in a drawing room and each manufacturing step in which a drawn photomask is used; Reading the calculated parameters, calculating the optimum scale factor by the temperature and humidity difference obtained from the temperature and humidity of each manufacturing process in which the drawing room and the drawn photomask are used, and calculating the calculated scale factor. Multiplying the drawing data, and outputting a control signal for drawing the photomask based on the drawing data multiplied by the scale factor, and drawing a photomask based on the control signal. A method for creating a photomask, comprising: 10. The method according to claim 1, wherein the scale factor is calculated based on temperature / humidity difference information obtained from temperature / humidity of each of the manufacturing steps in which the drawing room and the drawn photomask are used, and further using a photomask. 10. The photomask drawing method according to claim 9, wherein the calculation is performed by adding information on a temperature rise caused by a manufacturing facility used. 11. The photomask drawing method according to claim 9, wherein said storage means is capable of individually recognizing and storing temperature and humidity for each manufacturing process. 12. The photomask drawing method according to claim 8, wherein the calculation of the scale factor is performed based on an expansion / contraction coefficient corresponding to the temperature and humidity of the photomask material. 13. The photomask according to claim 8, wherein the drawing data includes attribute information specifying a manufacturing process in which the drawn photomask is used. Drawing method. 14. The method according to claim 8, wherein the drawing data is CAD data.