JP2007193541A - Analysis method for component mounting board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an analysis method for a component mounting board that can be expected to reduce the cost of calculations and enhance the accuracy of analysis. <P>SOLUTION: The analysis method includes a process (A) for creating a board layer shell model of a multilayer wiring board, a process (B) for creating a component layer shell model that is divided by an element dividing line according to the joint positions of components on the surface of the multilayer wiring board, a process (C) for redividing the mounting positions of the components of the base layer shell model, and a process (D) for forming an analytical model by coupling a board neutral surface with a component neutral surface by means of beam elements or solid elements that are joint elements equivalent to component mounting requirements. Boundary requirements are given to the analytical model and calculations are made. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for analyzing physical characteristics of a component mounting board in a state where components are mounted on a multilayer wiring board used for construction of electronic circuits of various electronic devices.

  Recently, for the purpose of downsizing electronic devices, multilayer wiring boards have been adopted in the construction of electronic circuits for high-density mounting of electronic components. As the wiring pattern of each layer of the multilayer wiring board, a multilayer wiring pattern satisfying electrical performance can be obtained by inputting circuit data to a computer-aided multilayer wiring board design CAD (Computer-Aided Design).

  However, the material of each layer of the multilayer wiring board and the width of the wiring pattern, in other words, the difference in the remaining ratio of the copper foil part of the wiring pattern, the difference in the rigidity of the electronic components incorporated inside, the position and number of via holes, the surface The mechanical performance of the completed component mounting board varies depending on the component mounted on the substrate and the mounting method of the component. Specifically, there is a possibility that a warpage exceeding a limit occurs in the component mounting board due to an applied external force or temperature change, and an operation failure occurs in the multilayer wiring board.

  Therefore, as is conventionally seen in (Patent Document 1) for multilayer wiring boards, a three-dimensional model is created for each layer based on the pattern and thickness data that are the outer shape of the board, and the three-dimensional model of each layer is stacked to form a board. Create an entire solid model, determine whether the shape change of the solid model when the external force or temperature change is given to this solid model is a tolerance deformation, and if the shape change exceeds the tolerance, The multi-layer wiring board satisfying the mechanical performance is designed by feeding back to the design stage by the CAD.

The concept of the “solid model” itself is a theory that has been established and adopted in the field of stress analysis of various three-dimensional industrial parts, and is detailed in (Non-Patent Document 1) and the like.
JP 2004-13437 A "Finite Element Method Handbook I Basic Edition" Kutsuo Awazu Hiroshi Miyamoto, Baifukan Co., Ltd. February 25, 1989 First edition 5th edition issued

  However, in order to expect a highly accurate analysis result, it is necessary to increase the number of divisions in the plane of each layer, and the number of elements becomes enormous, resulting in a calculation cost. When trying to analyze the mechanical performance of not only a multilayer wiring board but also a component mounting board in which components are mounted on the surface of the multilayer wiring board, the number of elements becomes enormous and the calculation cost further increases.

The allowable range of the vertical / horizontal size ratio of the outer shape of the multilayer wiring board is narrow, and when it is used for a thin multilayer wiring board, no improvement in accuracy can be expected for the calculation cost.
It is an object of the present invention to provide a component mounting board analysis method that can be expected to reduce calculation costs and improve analysis accuracy.

  The component mounting board analyzing method according to claim 1 of the present invention provides an outline of each layer of the multilayer wiring board and a wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. Generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line based on the above, and generating a substrate layered shell model in which the single layer model for each layer is stacked using thickness information of each layer (A), a step (B) for generating a component laminated shell model divided by element dividing lines based on the bonding position of the component to the surface of the multilayer wiring board, and a component laminated shell model used A step (C) of re-dividing the mounting position of the component of the board laminated shell model by the divided element dividing line, and a substrate neutral plane and a component laminated shell calculated from the re-divided board laminated shell model A step (D) of forming an analysis model by combining a component neutral surface calculated from Dell with a beam element or solid element that is a joint element equivalent to the mounting condition of the component, and a boundary condition for the analysis model And a step (E) for calculating deformation. FIG. 6 shows a claim correspondence diagram of claim 1.

  The component mounting board analyzing method according to claim 2 of the present invention is to analyze the external characteristics of the multilayer wiring board, the wiring pattern of each layer, and the parts when analyzing the physical characteristics of the component mounting board with the components mounted on the surface of the multilayer wiring board. Based on the position of the land where the surface is mounted, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is stacked using thickness information of each layer. A step (A-2) of generating a substrate stacking shell model, a step (B) of generating a component stacking shell model divided by element dividing lines based on the bonding position of the component to the surface of the multilayer wiring board, The substrate neutral surface calculated from the substrate stacking shell model and the component neutral surface calculated from the component stacking shell model are combined into a beam element or solid element which is a joint element equivalent to the mounting conditions of the component. In the binding to the step of forming the analysis model (D), characterized by a step (E) for calculating a deformation by applying boundary conditions to the analysis model. FIG. 16 is a diagram corresponding to the claim of claim 2 and is different from claim 1 in that neither the component nor the board is subdivided.

  According to a third aspect of the present invention, there is provided the component mounting board analyzing method according to the first or second aspect, wherein the substrate neutral surface and the component neutral surface are coupled with a beam element or a solid element as a joining element. In the step (D) of forming a model, the nodes of the resin-based bonding material area excluding the nodes connected by the beam element or the solid element which is the bonding element between the board lamination shell model and the component lamination shell model are described above. The analysis model is calculated by combining the resin-based bonding material in the resin-based bonding material area with bonding elements having equivalent mechanical strength.

  The component data library according to claim 4 of the present invention is a component data library in which data of the components used for analyzing physical characteristics of a component mounting board in which components are attached to the surface of a multilayer wiring board is accumulated. In addition, a component stacking shell model in which elements are divided based on the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board is recorded corresponding to each component. It is characterized by that.

  The analysis method for component mounting board according to claim 5 of the present invention is based on the outer shape of the multilayer wiring board and the wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. A step of generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line, and generating a substrate laminated shell model in which the single layer model for each layer is laminated using thickness information of each layer (A And a component stacking shell model obtained by dividing an element based on the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board, and corresponding to each component. A step (B-2) of reading out the component laminated shell model from the obtained component data library, and an actual state of the component of the substrate laminated shell model by an element dividing line of the component laminated shell model. The step (C) of subdividing the position, the board neutral surface calculated from the board laminated shell model, and the component neutral face calculated from the component laminated shell model are joint elements equivalent to the mounting conditions of the parts. The method includes a step (D) of forming an analysis model by combining beam elements or solid elements, and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. FIG. 17 shows a claim correspondence diagram of claim 5, which is different from claim 1 in that the parts data library according to claim 4 is used.

  According to a sixth aspect of the present invention, when analyzing the physical characteristics of a component mounting board having components mounted on the surface of the multilayer wiring board, the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the components Based on the position of the land where the surface is mounted, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is stacked using thickness information of each layer. A component laminated shell in which an element is divided based on the step (A-2) of generating a substrate laminated shell model, and the joint dividing line that passes through the joint position to the surface of the multilayer wiring board and the external shape and internal structure of the component A step (B-2) of reading out the component laminated shell model from a component data library in which the model is recorded corresponding to each component, and in the board calculated from the substrate laminated shell model (D) forming the analysis model by combining the surface and the component neutral surface calculated from the component stacking shell model with a beam element or solid element that is a joint element equivalent to the mounting condition of the component; And (E) calculating a deformation by giving a boundary condition to the model. FIG. 18 shows a claim correspondence diagram of claim 6, which is different from claim 2 in that the parts data library according to claim 4 is used.

  The component data library according to claim 7 of the present invention is a component data library in which data of the component is accumulated to analyze physical characteristics of a component mounting board in which the component is attached to the surface of the multilayer wiring board. Corresponding to the component neutral surface calculated from the component stacking shell model divided into elements based on the component outer shape, internal structure, and the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board Characterized by recording.

  The analysis method for component mounting board according to claim 8 of the present invention is based on the outer shape of the multilayer wiring board and the wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. A step of generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line, and generating a substrate laminated shell model in which the single layer model for each layer is laminated using thickness information of each layer (A ), And the component neutral plane calculated from the component stacking shell model divided by the element dividing line based on the component dividing line passing through the bonding position to the surface of the multilayer wiring board, the external shape of the component, the internal structure, The process of reading from the component data library recorded corresponding to the component (B-3) and the mounting position of the component of the substrate stacking shell model by using the component dividing line of the component stacking shell model are reproduced. A beam element or a solid element which is a joining element equivalent to a mounting condition of the component, the splitting step (C), and the substrate neutral surface calculated from the subdivided substrate laminated shell model and the component neutral surface. The method includes a step (D) of combining to form an analytical model and a step (E) of calculating a deformation by giving boundary conditions to the analytical model. FIG. 19 shows a claim correspondence diagram of claim 8, which is different from claim 1 in that the parts data library according to claim 7 is used.

  In the component mounting board analyzing method according to claim 9 of the present invention, when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board, the outer shape of the multilayer wiring board, the wiring pattern of each layer and the parts A single layer model for each layer is generated by dividing the inside of each layer by element dividing lines based on the position of the land where the surface is mounted, and the single layer model for each layer is stacked using the thickness information of each layer In the element dividing line based on the step (A-2) for generating the substrate stacking shell model, and the joining parting line passing through the joining position of the part to the surface of the multilayer wiring board, and the external shape and internal structure of the part The step (B-3) of reading the component neutral plane calculated from the divided component laminated shell model from the component data library recorded corresponding to the component, and the substrate laminated shell model A step (D) of forming an analysis model by combining a substrate neutral surface and the component neutral surface with a beam element or a solid element which is a joining element equivalent to a mounting condition of the component; And (E) for calculating deformation by giving a condition. FIG. 20 is a diagram corresponding to the claim of claim 9 and is different from claim 2 in that the parts data library of claim 7 is used.

  The component mounting board analyzing method according to claim 10 of the present invention is based on the outer shape of the multilayer wiring board and the wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. A step of generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line, and generating a substrate laminated shell model in which the single layer model for each layer is laminated using thickness information of each layer (A And (B) generating a component laminated shell model divided by the element dividing line based on the bonding position of the component to the surface of the multilayer wiring board, and mounting the component on the surface of the substrate laminated shell model When the component laminated shell model whose element dividing line does not match the position of the substrate laminated shell model at the position is joined, one of the model of the substrate laminated shell model and the component laminated shell model An intermediate file based on the distance from the intersection of the nearest element dividing line of the other model and the rigidity between them to connect the intersection of the other element dividing line to the intersection of the nearest element dividing line of the other model A beam element or a solid which is a joining element equivalent to the mounting condition of the component, the step (F) to be generated, and the substrate neutral surface calculated from the substrate laminated shell model and the component neutral surface calculated from the component laminated shell model The method includes a step (D-2) of forming an analysis model by combining elements with the joining intermediate file, and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. FIG. 21 shows the claim correspondence diagram of this claim 10, by using the generated bonding intermediate file without generating the board lamination shell model based on the position of the land on which the component is surface-mounted, For example, it is different from claim 2 in that the subdivision to match the component laminated shell model of the board laminated shell model is not required.

  The component mounting board analyzing method according to claim 11 of the present invention is based on the outer shape of the multilayer wiring board and the wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. A step of generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line, and generating a substrate laminated shell model in which the single layer model for each layer is laminated using thickness information of each layer (A And a component stacking shell model obtained by dividing an element based on the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board, and corresponding to each component. Reading out the component laminated shell model from the component data library (B-2), and mounting the component on the surface of the substrate laminated shell model at the board laminated shell model Is the nearest element division of the other model with the intersection of the element division lines of one model of the board lamination shell model and the component lamination shell model when the component lamination shell models whose element division lines do not match are joined A step (F) for generating a bonding intermediate file based on the distance from the intersection of the nearest element dividing line of the other model and the rigidity between them to be connected to the intersection of the lines, and the calculation from the substrate laminated shell model An analysis model is formed by combining the substrate neutral plane and the component neutral plane calculated from the component stacking shell model with a beam element or solid element, which is a bonding element equivalent to the mounting condition of the component, using the bonding intermediate file. The method includes a step (D-2) and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. FIG. 23 shows the claim correspondence diagram of this claim 11, by using the generated bonding intermediate file without generating the substrate laminated shell model based on the position of the land on which the component is surface-mounted, For example, it is different from claim 6 in that subdivision to match the component laminated shell model of the board laminated shell model is not required.

  The component mounting board analyzing method according to claim 12 of the present invention is based on the outer shape of the multilayer wiring board and the wiring pattern of each layer when analyzing the physical characteristics of the component mounting board having components mounted on the surface of the multilayer wiring board. A step of generating a single layer model for each layer obtained by dividing the inside of each layer by an element dividing line, and generating a substrate laminated shell model in which the single layer model for each layer is laminated using thickness information of each layer (A ), And the component neutrality calculated from the component stacking shell model divided by the element dividing line based on the component dividing line passing through the bonding position of the component to the surface of the multilayer wiring board. A step (B-3) of reading a surface from a component data library recorded corresponding to the component, and a board laminated shell model at the mounting position of the component on the surface of the substrate laminated shell model Is the nearest element division of the other model with the intersection of the element division lines of one model of the board lamination shell model and the component lamination shell model when the component lamination shell models whose element division lines do not match are joined A step (F) for generating a bonding intermediate file based on the distance from the intersection of the nearest element dividing line of the other model and the rigidity between them to be connected to the intersection of the lines, and the calculation from the substrate laminated shell model An analysis model is formed by combining the substrate neutral plane and the component neutral plane calculated from the component stacking shell model with a beam element or solid element, which is a bonding element equivalent to the mounting condition of the component, using the bonding intermediate file. The method includes a step (D-2) and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. FIG. 24 shows the claim correspondence diagram of this claim 12, by using the generated bonding intermediate file without generating the board lamination shell model based on the position of the land on which the component is surface-mounted. For example, it is different from claim 9 in that subdivision to match the component laminated shell model of the board laminated shell model is not required.

  According to a thirteenth aspect of the present invention, there is provided the component mounting board analysis program according to the first, second, fifth, sixth, eighth, ninth, tenth, tenth, eleventh, and tenth aspects. The component mounting board analysis method according to any one of 12 is configured to be executed.

  According to the component mounting board analysis method of the present invention, a single-layer model for each layer is generated based on the outer shape of the multilayer wiring board in which the material in the layer is non-uniform, and the composition of each layer, and based on this, a laminated shell model is generated. Without calculating the deformation by substituting boundary conditions into this laminated shell model, the neutral plane of the component laminated shell model and the neutral plane of the board laminated shell model are used as the component mounting conditions. Create an analytical model connected with beam elements or solid elements, which are equivalent joint elements, and apply boundary conditions to this analytical model to calculate the deformation. However, the amount of components mounted on the surface of the multilayer wiring board is affected by the multilayer wiring board even though the amount of calculation is small compared to the amount of calculation by the conventional analysis method. Not, it is possible to obtain good analytical results.

Hereinafter, the component mounting board analysis method of the present invention will be described based on specific embodiments.
(Embodiment 1)
FIG. 1 shows a flow of stress analysis based on the component mounting board analysis method.

  At the start of processing, the outer shape 1 of the multilayer wiring board to be analyzed and the wiring pattern data 2 of each layer are prepared as a first file M1, and in addition to the wiring patterns and vias, the components are included in the multilayer wiring board. In the case of being arranged inside the multilayer wiring board, the component type 3, the shape 4 and the position 5a are prepared as the second file M2. For the components mounted on the surface of the multilayer wiring board, the surface mount component data 5b described for each component with respect to the mounting method, shape, and structure is prepared as the second file M2. In the case of an integrated circuit, the shape of the surface mount component data 5b includes data on the package outer shape and the arrangement of external connection terminals. In the case of an integrated circuit, the structure records data such as the material of the package and the location of the chip inside the package. The data about the mounting position of the component on the surface of the multilayer wiring board is described in accordance with the surface mounting component data 5b for each component, or any multilayer wiring board is used and the surface of the multilayer wiring board is used. It is also possible to read and process from design CAD data of a computer-aided multilayer wiring board that manages which component is mounted at which mounting position. In this embodiment, description will be made on the assumption that data regarding the mounting position of a component and its component name is read from CAD data and processed.

  Specifically, the first file M1 divides the multilayer wiring board into first to nth layers as shown in FIG. 2, and the first layer, the third layer, the fifth layer,. The layer is a wiring layer, the second layer, the fourth layer,..., The (n−1) th is an insulating layer.

First, an analysis of a state in which no component is mounted on the surface of the multilayer wiring board will be described as a basic state.
In step S101 of the electronic computer 6 in this basic state, element division processing is executed based on the first file M1. In the element dividing process, each wiring layer of the first layer, the third layer, the fifth layer,... Is divided into a plurality of cells. A specific example of the first wiring layer is shown in FIG. In this figure, a copper foil pattern 8 having a desired shape is formed on a base material 7. In this case, in step S101, as shown in FIG. 3B, the plane of the first wiring layer is divided into cells of the same size and divided into elements.

  In step S102, with respect to the divided data of each cell obtained by dividing the element in step S101, based on the data of the element material type, etc., as shown in FIG. The element determination of each cell is performed based on a preset threshold value such that “less than 50% of cells” are “no copper foil and only the base material”. The material type assignment result is shown in FIG.

  For the remaining wiring layers of the third wiring layer, the fifth wiring layer,... In which the base material and the copper foil are mixed, material type assignment is executed under the same conditions as in the first wiring layer. Vias that connect the lower wiring layer and the upper wiring layer even when the element material type in the plane is constant, such as the second layer, the fourth layer,..., The (n-1) th insulating layer. Similarly, the element determination of each cell is performed depending on whether or not there is.

  At this time, for all the layers from the first layer to the n-th layer, the shape and size of the cell are the same, and the intersection GX of the element dividing lines 24 dividing the plane of each wiring layer into cells. The coordinate positions of are consistent.

  In this way, after the assignment of the material type for each layer is finished and the third file M3 is filed as the divided data 9 and the element material type data 10, an analysis model creation process is executed in step S103. Specifically, the thickness data of each layer and the stacking order based on the first file M1 are given to the two-dimensional data of each layer created by the processing up to step S102, and FIG. 4 (a) to FIG. 4 (b). As shown, a three-dimensional substrate laminate shell model 11 is created and filed as the substrate laminate shell model 11 in the fourth file M4 in step S104.

  When components other than wiring patterns and vias are arranged in the multilayer wiring board, the corresponding to the stacked shell model created in step S103 based on the component type, shape and position of the second file M2. The laminated shell model data 11 is incorporated at the position.

In the fourth file M4, boundary conditions 12 representing conditions for the purpose of analysis and material properties 13 of each material of the multilayer wiring board are read in advance based on the first file.
The boundary condition 12 required when using the finite element method includes a constraint condition and a load condition. The constraint condition represents a state in which the multilayer wiring board of the analysis object is attached and supported. The load condition includes a mechanical load due to a mechanical force applied to somewhere in the multilayer wiring board and a temperature load due to a force generated from expansion / contraction of an analysis object caused by a temperature change.

  The material physical properties 13 are eigenvalues for each material constituting the multilayer wiring board to be analyzed. Mainly, Young's modulus, Poisson's ratio, linear expansion coefficient, thermal conductivity, specific heat, density, and radiation rate for each material. , Heat transfer coefficient etc. are read.

  In step S105, a two-dimensional model of the reference plane of the three-dimensional laminated shell model is calculated based on the substrate laminated shell model 11 in the fourth file M4 and the material properties 13 in the fourth file M4. Specifically, as shown in FIG. 5A, a virtual substrate neutral plane 14 existing in the three-dimensional substrate laminated shell model 11 is calculated. It is assumed that the position of the substrate neutral surface 14 is a distance d1 from the upper surface of the substrate laminated shell model 11 and a distance d2 from the lower surface of the substrate laminated shell model 11.

  Further, in this step S105, the deformation of the substrate neutral surface 14 when the boundary condition 12 is given to the substrate neutral surface 14 is calculated, and the deformed neutral surface is assumed to be 14A shown in FIG. A deformation 11A of the multilayer wiring board is obtained by adding the distances d1 and d2 based on the plate thickness to one surface and the other surface of the deformed substrate neutral surface 14A.

  Further, in this step S105, in the case of stress analysis, the stress of each layer of the first layer to the n-th layer is obtained by using the deformation 11A and the thickness information of each layer and the physical properties of Young's modulus, Poisson's ratio, and thermal expansion coefficient. Calculate

  Further, in order to conduct a heat conduction analysis in this step S105, temperature conditions are given to the upper and lower surfaces of the laminated shell, and the thickness, thermal conductivity, specific heat, and density properties of each layer as the thickness information are determined. The temperature of each layer of the first layer to the n-th layer is calculated by using the temperature, and the temperature of the substrate laminated shell model 11 is calculated.

  In step S106, the result of the deformation 11A in step S105 is read into the fifth file M5 as the warp (displacement) 15 and the stress 16 of each layer. The temperature of the substrate laminated shell model 11 is also read into the fifth file M5.

  In step S107, the fifth file M5 in step S106 is read to determine whether the deformation and temperature of the analysis result satisfy the condition. If the condition is not satisfied, the data relating to the production to be analyzed is written. A part of the parameters of the CAD data 17 of the sixth file M6 is changed, the first file M1 and the second file M2 are changed based on this, and the above analysis is repeated. If the condition is satisfied, the data is output to computer-aided manufacturing (CAM) data 18 of computer-aided manufacturing.

  As described above, in step S105, the three-dimensional laminated shell model 11 is converted to a neutral plane, the boundary condition 12 is applied to the substrate neutral plane 14, two-dimensional deformation and temperature are calculated, and thickness information is added. Since it can be analyzed by the calculation process of obtaining the outer shape of the multilayer wiring board, it takes less calculation time than the conventional analysis that calculates the three-dimensional deformation by applying the boundary condition to the three-dimensional solid model. The analysis result with almost the same accuracy can be obtained.

  The above is the basic state of analysis in which no component is mounted on the surface of the multilayer wiring board, but when the component is mounted on the surface of the multilayer wiring substrate, the first claim correspondence diagram shown in FIG. Processed based on.

  In the process (A) of the first claim correspondence diagram, it is the same that the substrate laminated shell model 11 is created and written in the fourth file M4 in step S103 of the electronic computer 6, but 3 in step S105 of the electronic computer 6 In the case where the calculation process is performed by applying the boundary condition 12 to the substrate neutral plane 14 from the three-dimensional laminated shell model, when the component is mounted on the surface of the multilayer wiring board, the process of the first claim correspondence diagram ( The surface of the multilayer wiring board determined by the mounting method and the arrangement of the electrical connection terminals of each component from the second file M2 in accordance with the components mounted on the surface of the multilayer wiring board in place of B) to (D) Further, the data 5b of the joining position is read, and the following processing is executed based on this data.

-Creation of component laminated shell model 19 for components mounted on the surface of multilayer wiring board-Subdivision of substrate laminated shell model 11-Connection of substrate laminated shell model 11 and component laminated shell model 19 This will be described in detail.

− Creation of component laminated shell model 19 −
This step (B) is executed in step S103. The surface mount component data 5b of the second file M2 is searched with the component name read from the CAD data as a component mounted on the surface of the multilayer wiring board, and the corresponding component identified by this is as shown in FIG. In the case of a QFP (Quad Flat Package) integrated circuit, a portion having the same in-plane direction (XY plane) structure is considered as one layer, and the structure (material) is different in the direction away from the multilayer wiring board (Z direction). Define a layer for each. Here, as shown in FIG. 7B, the layer including the built-in IC chip 20 is the second layer, the lower layer is the first layer, and the upper layer is the third layer. In the first layer, external connection terminals 21 are provided around the lands on the surface of the multilayer wiring board as shown in FIG. Whereas the first layer and the third layer are composed of only the package material, the second layer is composed of the IC chip 20 having different mechanical characteristics.

  First, the second layer shown in FIG. 8A is divided into meshes in the in-plane direction as shown in FIG. 8B. Here, mesh division is performed with reference to a dividing line 22 that passes through the position of the external connection terminal 21 in the first layer. Next, as shown in FIG. 8 (c), the second layer is further divided into meshes as shown in FIG. 8 (d) with an additional dividing line 23 on the basis of the side 20a of the IC chip 20, and each divided area is divided. Perform material type assignment. Even in the case where the element material types in the plane are constant as in the first layer and the third layer, mesh division is performed by the same dividing line as in FIG. 8D, and material types are assigned to each area.

  The single layer model of the first layer to the third layer of the component thus created gives the thickness data of each layer and the stacking order, and the three-dimensional component stacking shell model 19 as shown in FIG. And is filed as the component stacking shell model 19 in the fourth file M4 in step S104.

− Subdivision of substrate stacking shell model 11 −
This step (C) is executed in step S103.
Subdivision of the substrate laminated shell model 11 is performed by dividing the substrate laminated shell model 11 divided at the present time into the fourth file M4 based on the structure of the single multilayer wiring board as shown in FIG. 9A. It is assumed that the substrate material 7 and the copper wiring 8 are divided by the line 24.

  As shown in FIG. 9B, meshes of the element dividing lines 22 and 23 on the component laminated shell model 19 side are overlaid on the component mounting positions read from the CAD data, so that all layers of the substrate laminated shell model 11 are obtained. 9D is further divided by the new element dividing lines 251 to 2511 that match the meshes of the component dividing lines 22 and 23 on the component side as shown in FIG. The contents of the substrate laminated shell model 11 in the file M4 are updated.

− Coupling of substrate laminate shell model 11 and component laminate shell model 19 −
This step (D) is executed in step S105.
FIG. 10A shows a state in which the component laminated shell model 19 is stacked at the mounting position of the substrate laminated shell model 11, and FIG. 10B shows an enlarged view of the component at the component mounting position and the multilayer wiring board. Yes. The respective calculations of the substrate neutral surface 14 (see FIG. 5B) of the substrate laminated shell model 11 and the component neutral surface 26 (see FIG. 10C) of the component laminated shell model 19 are calculated as substrate neutral. At the time of calculation of the surface 14, the material physical property value of each element divided by the element dividing line 24 of each layer of the substrate laminated shell model 11 is read from the material physical property 13 of the fourth file M4 and substituted to execute the calculation. When calculating the component neutral plane 26, the material physical property values of each element delimited by the element dividing lines 22 and 23 of each layer of the component laminated shell model 19 are read from the material physical property 13 of the fourth file M4 and substituted. Calculation is performed.

  In the case of a QFP integrated circuit, the component is mounted on the multilayer wiring board because each external connection terminal 21 of the component is soldered to the land 27 of the multilayer wiring board as shown in FIG. As shown in FIG. 10 (c), an analytical model 29 is created by combining them integrally with a cylindrical beam element 28 as a joining element equivalent to soldering.

  Specifically, since the meshes of the element dividing lines of the board laminated shell model 11 and the part laminated shell model 19 are completely coincident with each other, the mesh node at the position of each external connection terminal 21 on the part neutral surface 26 and the board The mesh nodes at the positions of the lands 27 of the component mounting positions of the neutral plane 14 are coupled by beam elements 28, respectively.

  The shape of the beam element 28 is set in accordance with the terminal of the component and its shape. Even in the case of the same soldering, the lead wire is drawn out from the package instead of the terminal. A square pole is used as the beam element 28.

  In the above description, the case where the non-conductive film, non-conductive paste, or underfill resin as a resin-based bonding material is not filled between the component and the multilayer wiring board is taken as an example. Although the case where the vertical surface 26 and the substrate neutral surface 14 are connected as shown in FIG. 11A by using only the cylindrical beam element 28 has been described, this is based on MCM (Multi Chip Module) and BGA (Ball Grid Array). As a resin-based bonding material between a component such as CSP (Chip Size Package) and a multilayer wiring board, for example, when the underfill resin is filled, the component neutral surface is formed only by the cylindrical beam element 28. 26 and the substrate neutral surface 14 are not connected. As shown in FIG. 11B, a mesh node surrounded by the plurality of beam elements 28 having a cylindrical shape is further provided on the component neutral surface 26. And the substrate neutral plane 14 The mesh nodes are joined as, for example, square prism beam elements 30 as joint elements equivalent to the resin-based joint material, and the material properties of the underfill resin are assigned to the square pillar beam elements 30 in the material of the fourth file M4. An analysis model is created by reading out from the physical property 13 and substituting it, and the step (E) is executed.

  In this way, the analysis model of the multilayer wiring board with components created through the steps (B), (C), and (D) is further subjected to step S105 (step (E) in the claim correspondence diagram of FIG. 6). Then, the boundary condition 12 can be applied to the analysis model 29 to calculate the two-dimensional deformation and temperature, and the analysis can be performed by a calculation process step of obtaining the outer shape of the multilayer wiring board by adding the thickness information. Compared to an analysis in which boundary conditions are applied to a solid model to calculate a three-dimensional deformation, an analysis result with almost the same accuracy can be obtained in a short calculation time.

Further, not only the analysis of the multilayer wiring board in a state where the component is surface-mounted, but also the deformation that actually acts on the component due to the deformation of the multilayer wiring board can be analyzed.
In the above description, as shown in FIG. 25, the substrate neutral surface 14 of the substrate laminated shell model 11 and the component neutral surface 26 of the component laminated shell model 19 are coupled by the beam element 28 as a joining element. The model 29 has been described as an example. However, in the case where the multilayer wiring board and the component are joined by bumps such as solder balls, the joining element is not the beam element 28 but as shown in FIG. More accurate analysis results can be obtained by using the analysis model 29 coupled by the solid elements 31.

(Embodiment 2)
In the element material determination step shown in FIG. 3C of the above embodiment, the ratio of the base material 7 and the copper foil pattern 8 is set for one cell in which the base material 7 and the copper foil pattern 8 are mixed. Accordingly, the material property values were determined as “all are base materials 7” or “all are copper foil patterns 8”, and the processing was simplified, but in this (Embodiment 2), the copper foil patterns 8 of each cell. The only difference is that the material property values are individually determined and processed according to the wiring width.

12 and 13 show (Embodiment 2).
FIG. 12 shows a processing routine for determining the material of each cell A in the plane of the single layer model by automatic processing in the single layer model shown in FIG.

  In steps S1 to S11 in FIG. 12, each cell A is scanned in the x-axis direction as shown in FIG. 13B, and the remaining copper ratio in the y-axis direction of the copper foil pattern 8 is calculated. In steps S12 to S17, each cell A is scanned in the y-axis direction as shown in FIG. 13C to calculate the remaining copper ratio of the copper foil pattern 8 in the x-axis direction.

Specifically, in step S1, the default value j = 0 is set so that the single-layer model that starts the calculation determines one of the first layer to the n-th layer.
In step S2, the default value j = 0 in step S1 is incremented, and the calculation for the first layer is declared.

  In step S3, the first-layer wiring pattern designated by j = 1 incremented in step S2 in the wiring pattern data 2 of each layer, as shown in FIG. Divide into

In step S4, a default value i = 0 is set in order to determine the cell A from which the calculation is started.
In step S5, it is declared that the default value i = 0 in step S4 is incremented and calculation is performed for cell A with element number 1.

In step S6, a default value k = 0 is set in order to declare the scanning position in the x-axis direction in the cell declared in step S5.
In step S7, it is declared that the default value k = 0 in step S6 is incremented to calculate the wiring width at each position in the x-axis direction in the cell A with element number 1.

In step S8, the length Ry1 of the copper foil pattern 8 in the y-axis direction when the position of the cell A of element number 1 in the x-axis direction is k = 1 is calculated.
In step S9, it is checked whether all the positions in the x-axis direction of the cell A with the element number 1 are calculated. Since k = 1 here, returning to step S7, the routine of steps S7 and S8 is repeated, and when calculation is completed for all the positions in the x-axis direction of the cell A with element number 1, this step S9 Exit from the routine and execute step S10.

  If the length of the side of the cell A is “1”, the abundance of copper remaining in the y-axis direction is the average value of the lengths Ry1 to RyN, and this is the average remaining copper ratio in the y-axis direction. In step S10, an average value Vfy of the lengths in the y-axis direction of the copper foil patterns 8 at the respective positions obtained so far in step S8 is calculated.

Vfy = (Ry1 + Ry2 +... + RyN) / N
In step S11, an equivalent property value Ey in the y-axis direction is calculated.
Ey = EB (1−Vfy) + ECU · Vfy
Note that EB is a physical property value of the base material 7, and ECU is a physical property value of the copper foil pattern 8.

In step S12, a default value k = 0 is set in order to declare the scanning position in the y-axis direction.
In step S13, it is declared that the default value k = 0 in step S12 is incremented to calculate the wiring width at each position in the y-axis direction in the cell A with element number 1.

In step S14, as shown in FIG. 13C, the length Rx1 in the x-axis direction of the copper foil pattern 8 at the position in the y-axis direction of the cell A with element number 1 is calculated as k = 1.
In step S15, it is checked whether all the positions in the y-axis direction of cell A with element number 1 have been calculated. Here, since k = 1, the routine returns to step S13 and the routines of steps S13 and S14 are repeated, and when the calculation for all the positions in the y-axis direction of the cell A with the element number 1 is completed, this is determined in step S15. Step S16 is executed after exiting the routine.

In step S16, the average value Vfx of the length in the x-axis direction of the copper foil pattern 8 at each position obtained so far in step S14 is calculated.
Vfx = (Rx1 + Rx2 +... + RxN) / N
In step S17, an equivalent property value Ex in the x-axis direction is calculated.

Ex = EB (1-Vfx) + ECU · Vfx
In step S18, the material property values corresponding to the wiring width are written in the fourth file M4 shown in FIG. 1 in association with the cell A of the element number 1 in the first layer declared in steps S2 and S5.

  In step S19, it is checked whether step S18 has been performed for all cells A in the first layer declared in step S5. Here, since i = 1, the process returns to step S5 and increments to i = 2, and the routine up to step S18 is repeated for the cell A with the element number 2 in the first layer, and the cell A with the element number 2 When the calculation is finished, the routine is exited in step S17 and step S20 is executed.

  In step S20, it is checked whether step S18 has been performed for all the layers 1 to m stacked. Since j = 1 here, the process returns to step S2, increments to j = 2, repeats the routine up to step S18 for the second to m-th layers, and completes the calculation for the m-th layer. Then, the process exits from this routine and completes the material property collecting process corresponding to the wiring width.

  Thus, since the material physical property is determined according to the wiring width in each cell, the deformation of the substrate neutral surface 14 is calculated based on the material physical property 13, and one surface of the substrate neutral surface 14 is further calculated. By adding a plate thickness to the other surface to obtain the outer shape of the multilayer wiring board, a more accurate analysis can be realized.

(Embodiment 3)
In each of the above-described embodiments, it has been described that the cell shape and size of the element division in the plane of all the single-layer models are the same. The model size can be reduced by making the shape and size of the element division cell in the plane of the model different from other ranges.

  That is, the area where the base material 7 and the copper foil pattern 8 are mixed divides the size of the cell A smaller than the area occupied by only the material of the base material 7 or the copper foil pattern 8 alone. .

  Specifically, the remaining copper ratio is read from the wiring pattern data 2 of each layer of the first file M1 for each cell that is roughly divided in advance, and the remaining copper ratio of 20% or less is occupied by the base material 7. The coarsely divided cells are not further divided finely. The remaining copper ratio of 80% or more is considered to be occupied by the copper foil pattern 8, and the coarsely divided cells are not further finely divided. For the remaining copper ratio of 20% or more and less than 80%, it is considered that the base material 7 and the copper foil pattern 8 are mixed, and the inside of the roughly divided cells is finely subdivided.

  The above process is repeated for the fine cells after the subdivision, and for the remaining copper ratio of 20% or more and less than 80%, the process of subdividing the inside of the cells after the subdivision further finely is repeated. FIG. 14A shows a single-layer model before division, FIG. 14B shows a single-layer model after subdivision, and the size of meshes represents the difference in cell size.

A flowchart of the process in this case is shown in FIG.
In step S1, the single layer model is divided into equal intervals with a minimum number of divisions. Here, the initial division is 4 × 4 as shown in FIG.

In step S2, four cells S11, S12, S13, and S14 in the x-axis direction are collectively selected as shown in (b).
In step S3, all of the cells S11 to S14 extracted in step S2 are left as shown in (c) from the wiring pattern data of the substrate CAD, specifically, the wiring pattern data 2 of each layer of the first file M1. Calculate the copper ratio. In this example, all the cells S11 to S13 had a remaining copper ratio of 25%, and the remaining copper ratio of the cell S14 was 50%.

  In step S4, it is checked whether the remaining copper ratio calculated in step S3 is 20% or less or 80% or more. In this example, “NO” is determined in step S4, and step S5 is executed. In step S5, as shown in (d), it is subdivided into two in the axial direction, and step S6 is executed. If “YES” is determined in the step S4, otherwise, the process skips the step S5 and executes the step S6.

  In step S6, it is checked whether the routine between step S2 and step S6 has been executed for all the row elements of the single layer model shown in (a), and the routine between step S2 and step S6 for all single layer models. When the necessary subdivision is completed, step S7 is executed next.

In step S7, four cells S11, S21, S31, and S41 in the y-axis direction are collectively selected as shown in FIG.
In step S8, the remaining copper ratio is calculated for all the cells S11 to S41 extracted in step S7 as shown in (f) from the wiring pattern data 2 of each layer of the first file M1. In this example, the remaining copper ratios of the cells S11, S21, S31, and S41 were 20%, 15%, 10%, and 20%.

  In step S9, it is checked whether the remaining copper ratio calculated in step S8 is 20% or less or 80% or more. In this example, “YES” is determined in step S9, and step S10 is skipped and step S11 is executed. If the remaining copper ratio of all the elements calculated in step S8 is not 20% or less or 80% or more, “NO” is determined in step S9, and step S10 is executed. When step S10 is executed, the image is subdivided in the y-axis direction as indicated by a virtual line in (g).

  In step S11, it is checked whether the routine between step S2 and step S6 has been executed for all of the column elements of the single layer model shown in (a), and the routine between step S7 and step S11 is performed for all single layer models. When the necessary subdivision is completed, step S12 is executed next.

In step S12, element numbers are assigned to the cells re-divided in the above flow and are handled as cells.
In step S13, it is checked whether at least one of step S5 and step S10 has been executed. If one of them has been executed, the process returns to step S2 and the process is repeated.

The substrate stacking shell model 11 is created by executing the processing of FIG. 15 on the single layer model of each layer.
In this way, the layout of the wiring pattern is complicated, and the area for which the warp (displacement) is to be accurately calculated is fine, and the other area is coarsely divided into meshes. In other words, the in-plane deformation does not occur or is small. By making the shape and size of the element division cell in the plane of the single-layer model different from other ranges, the number of cells appropriate for the layout of the wiring pattern can be used with less calculation time and accuracy. Good analysis results can be obtained.

  Note that, as a constraint condition for mesh division in FIG. 15, it is necessary that the division shapes in the layer direction are all the same and that the division is performed in an orthogonal system. Therefore, when creating a multilayer shell model of a multilayer wiring board, all the layers are re-launched according to the minimum cell size for elements with different division shapes in the layer direction when each single-layer model is stacked. In step S2 and S7 in FIG. 15, the row elements selected in the x-axis direction are not only single-layer cells S11 to S14 but also S11 to S14 and S11 to S41 of all layers, All of these elements are to be checked for the remaining copper ratio in subsequent steps S4 and S8, and the division in step S12 is reflected in all layers.

In each of the above-described embodiments, the case where the plate-like body is a plate having a flat surface has been described as an example. However, even a plate having a curvature can be similarly implemented.
In the component mounting board analysis method of each of the above embodiments, as shown in FIG. 6, the substrate laminated shell model is subdivided with the mesh of the component dividing lines of the component laminated shell model in step (C). With the configuration as shown in FIG. 5, the step (C) of subdivision of the substrate laminated shell model can be eliminated.

  Specifically, the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land 27 on which the component is surface-mounted (equal to the position of the bonding dividing line passing through the bonding position of the component to the surface of the multilayer wiring board) A single layer model for each layer obtained by dividing the inside of each layer by an element dividing line is generated, and the single layer model for each layer is generated using the thickness information of each layer of the multilayer wiring substrate. A step (A-2) for generating a substrate laminated shell model laminated in a shape, and a component laminated shell model divided by element dividing lines based on the joining position of the component to the surface of the multilayer wiring board of the component are created. The process (B) and the board neutral plane calculated from the board stacking shell model and the component neutral plane calculated from the part stacking shell model are coupled by a joining element equivalent to the mounting condition of the component. And step (D) to form the LE 29, constituting out with step (E) for calculating the deformation in the analysis model 29 gives the boundary conditions. The step (B) may be performed before the step (A-2).

  In the component mounting board analysis method of each of the above embodiments, each time a component is mounted on a multilayer wiring board, the component data is read from the second file M2 to create a component stacking shell model and write it to the fourth file M4. However, this is a component laminated shell in which the element is divided into the second file M2 as data for each component based on the outline, the internal structure, and the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board. By preparing a part data library in which a model is recorded corresponding to each part, the work load of the electronic computer 6 can be further reduced.

Specifically, it is executed as shown in FIG.
The component mounting board analysis method shown in FIG. 17 is a modification of FIG. 6. In this case, each layer obtained by dividing each layer by element dividing lines based on the outer shape of the multilayer wiring board and the wiring pattern of each layer. Generating a single layer model of each of the layers, and generating a substrate laminated shell model in which the single layer model for each layer is laminated in the shape of the multilayer wiring board using thickness information of each layer of the multilayer wiring board (A ) And the component stacking shell model in which the components are divided based on the joining dividing line passing through the joining position of the component to the surface of the multilayer wiring board, and the external shape of the component, and the internal structure are recorded corresponding to each component. A step (B-2) of reading out the component laminated shell model from the component data library, and re-dividing the mounting position of the component in the substrate laminated shell model by the element dividing line of the component laminated shell model (C), a substrate neutral surface calculated from the substrate laminated shell model, and the component neutral surface calculated from the component laminated shell model are connected by a joining element equivalent to the mounting condition of the component, and the analysis model And a step (E) of calculating a deformation by giving a boundary condition to the analysis model.

  The component mounting board analysis method shown in FIG. 18 is a modification of FIG. 16. In this case, the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land on which the component is surface-mounted (= multilayer wiring) A single layer model for each layer obtained by dividing the inside of each layer by an element dividing line on the basis of a bonding dividing line that passes through the bonding position of the component to the surface of the substrate), and the single layer model for each layer is generated as the multilayer A step (A-2) of generating a substrate laminated shell model laminated in the shape of the multilayer wiring board using thickness information of each layer of the wiring board, the external shape of the component, the internal structure, and the surface of the multilayer wiring board The component laminated shell model is recorded from the component data library in which the component laminated shell model obtained by dividing the element based on the joining dividing line passing through the joining position of the component to the component is recorded corresponding to each component. The step (B-2) of projecting, and the substrate neutral surface calculated from the substrate laminated shell model and the component neutral surface calculated from the component laminated shell model are combined with a joining element equivalent to the mounting condition of the component. A step (D) of forming an analysis model, and a step (E) of calculating a deformation by giving a boundary condition to the analysis model.

  In the component mounting board analysis method of each of the above embodiments, the component neutral surface 26 is calculated each time when mounting on the multilayer wiring board. This is calculated as data for each part in the second file M2. By preparing a component data library in which the neutral surface 26 is recorded corresponding to each component, the work load of the electronic computer 6 can be further reduced.

Specifically, it is executed as shown in FIG. 19 or FIG.
The component mounting board analysis method shown in FIG. 19 is a modification of FIG. 6. In this case, each layer obtained by dividing each layer by element dividing lines based on the outer shape of the multilayer wiring board and the wiring pattern of each layer. Generating a single layer model of each of the layers, and generating a substrate laminated shell model in which the single layer model for each layer is laminated in the shape of the multilayer wiring board using thickness information of each layer of the multilayer wiring board (A ) And the component neutral plane calculated from the component stacking shell model divided by the element dividing line based on the component dividing line passing through the bonding position of the component to the surface of the multilayer wiring board. Is read out from the component data library recorded corresponding to the component (B-3), and the mounting position of the component of the board laminated shell model is subdivided by the element dividing line of the component laminated shell model And combining the substrate neutral surface calculated from the subdivided substrate laminated shell model and the component neutral surface with a joining element equivalent to the mounting condition of the component to form an analysis model The method includes a step (D) and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. The step (B-2) may be performed before the step (A-2).

  The component mounting board analysis method shown in FIG. 20 is a modification of FIG. 16. In this case, the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land on which the component is surface-mounted (multilayer wiring board) A single layer model for each layer obtained by dividing the inside of each layer by an element dividing line on the basis of a joining dividing line that passes through the joining position of the component to the surface of the layer, and the single layer model for each layer is generated by the multilayer wiring. A step (A-2) of generating a substrate lamination shell model laminated in the shape of the multilayer wiring board using thickness information of each layer of the board, and the external shape of the component, the internal structure, and the surface of the multilayer wiring board The part neutral plane calculated from the part stacking shell model divided by the element parting line based on the parting line passing through the part joining position is read from the part data library recorded corresponding to the part. And a step (B-3) of combining the substrate neutral surface calculated from the substrate laminated shell model and the component neutral surface with a joining element equivalent to a mounting condition of the component to form an analysis model ( D) and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. The step (B-3) may be performed before the step (A-2).

  In the step (D) shown in FIGS. 16, 17, 18, 19, and 20, the substrate neutral surface 14 of the substrate laminated shell model 11 and the components of the component laminated shell model 19 are processed as shown in FIG. In the case where the rising surface 26 is an analysis model 29 coupled with a beam element 28 as a joining element, or the multilayer wiring board and the component are joined by bumps such as solder balls, the joining element is used as a beam. Instead of the element 28, an analysis model 29 coupled by a solid element 31 can be used as shown in FIG.

  In FIG. 16, FIG. 18, and FIG. 20 described above, in order to eliminate the process of subdivision of the board stacking shell model, “the position of the land on which the component is surface-mounted (the component on the surface of the multilayer wiring board). A single-layer model is generated for each layer in which each layer is divided by element dividing lines on the basis of the bonding dividing line passing through the bonding position ”. However, by configuring as shown in FIG. 21 and FIG. The process of subdivision of the model can be eliminated.

  As shown in FIG. 21, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, and the single layer model for each layer is A step (A) of generating a board laminated shell model laminated in the shape of the multilayer wiring board using thickness information of each layer of the multilayer wiring board, and a position where the component is bonded to the surface of the multilayer wiring board; (B) for generating a component laminated shell model divided by element dividing lines based on the above, and the position of the element dividing line does not match the board laminated shell model at the mounting position of the component on the surface of the substrate laminated shell model When the component laminated shell model is joined, the intersection of the element dividing lines of one of the substrate laminated shell model and one of the component laminated shell models (for example, the component) is the other (for example, the substrate). Generating a joint intermediate file based on the distance between the intersection of the nearest element parting line of the model of the other (for example, the substrate) and the rigidity between them to connect to the intersection of the nearest parting line of the model ( F) and the board neutral plane calculated from the board stacking shell model and the component neutral plane calculated from the part stacking shell model are combined and analyzed with the joining element equivalent to the mounting condition of the part and the joining intermediate file. The method includes a step (D-2) of forming a model and a step (E) of calculating a deformation by giving a boundary condition to the analysis model. The step (B) may be performed before the step (A).

  Specifically, as shown in FIG. 22A, the board stacking shell model 11 and the part stacking shell model 19 to be combined in the step (D-2) are the components mounting position elements of the board stacking shell model 11. Since the mesh of the dividing line and the mesh of the element dividing line of the component laminated shell model 19 do not coincide with each other, in the step (F), the external connection terminal 21 of the component laminated shell model 19 is shown in FIG. In the case where the tip of the beam element 28 connected to the position P2 is P1, the length of the beam element 28 is l1, the rigidity of the beam element 28 is k1, and the component stacking shell model 19 is mounted at the component mounting position of the substrate stacking shell model 11 Further, the position of the substrate laminated shell model 11 where the tip P1 of the beam element 28 abuts is defined as P1a, and the mesh of the element dividing lines in the substrate laminated shell model 11 is changed. P3, P4, the distance between the position P1a and the intersection P3 is 12, the rigidity between the position P1a and the intersection P3 is k2, the distance between the position P1a and the intersection P4 is 13, and the distance between the position P1a and the intersection P4 The joining intermediate file is created in consideration of the distances l1, l2, and l3 and the stiffnesses k1, k2, and k3, where the rigidity is k3.

  In the step (D-2), the board neutral surface 14 calculated from the board stacking shell model 11 and the joining element equivalent to the component mounting condition calculated from the part stacking shell model 19 and the joining intermediate file are used. To join. As a result, the force generated at the coupling point P1a is distributed to the nodes P1, P3, and P4, so that the element dividing line mesh at the component mounting position of the board laminated shell model 11 and the element dividing line mesh of the component laminated shell model 19 A state equivalent to the state of matching can be created, and a target analysis model can be obtained without performing the re-division. In step (E), a boundary condition is given to the analysis model created in step (D-2) to calculate deformation. Note that the step (B) in FIG. 21 may be performed before the step (A).

  In the step (D-2), as shown in FIG. 25, the substrate neutral surface 14 of the substrate laminated shell model 11 and the component neutral surface 26 of the component laminated shell model 19 are connected to a beam element 28 as a joining element. However, when the multilayer wiring board and the component are bonded by bumps such as solder balls, the bonding element is not the beam element 28 but a solid element as shown in FIG. Even when the analysis model 29 coupled by the element 31 is used, the analysis can be performed by coupling using the joining intermediate file.

In the case of FIGS. 18 and 20, the use of the joining intermediate file is the same as in FIG.
In the case of FIG. 18, as shown in FIG. 23, in step (A), a single-layer model for each layer is generated in which each layer is divided by element dividing lines based on the outer shape of the multilayer wiring board and the wiring pattern of each layer. Then, a single-layer model for each layer is generated using the thickness information of each layer of the multilayer wiring board to form a multilayer board shell model. In step (B-2), a component stacking shell model obtained by dividing an element on the basis of the joint dividing line passing through the joint position of the component to the surface of the multilayer wiring board is used for each component. The part stacking shell model is read out from the correspondingly recorded part data library. In the step (F), when the component laminated shell model in which the position of the element dividing line does not coincide with the substrate laminated shell model at the mounting position of the component on the surface of the substrate laminated shell model, The distance between the intersection of the element division line of one model of the component stacking shell model and the intersection of the nearest element division line of the other model to join the intersection of the element division line of the other model A joining intermediate file is generated based on the rigidity between them. In the step (D-2), the board neutral plane calculated from the board laminated shell model and the component neutral plane calculated from the component laminated shell model are combined with a joining element equivalent to the mounting condition of the parts and the joining intermediate file. Combine to form an analytical model. In step (E), boundary conditions are given to the analysis model to calculate deformation. Note that the step (B-2) of FIG. 23 may be performed before the step (A).

  In the case of FIG. 20, as shown in FIG. 24, in step (A), a single-layer model for each layer obtained by dividing each layer with element dividing lines based on the outer shape of the multilayer wiring board and the wiring pattern of each layer is generated. A single layer model for each layer is generated, and a substrate stacking shell model is generated by stacking the single layer model in the shape of the multilayer wiring substrate using the thickness information of each layer of the multilayer wiring substrate. In the step (B-3), calculation is performed from the component stacking shell model divided by the element dividing line based on the outer shape of the component, the internal structure, and the bonding dividing line passing through the bonding position of the component to the surface of the multilayer wiring board. The part neutral plane is read out from the part data library recorded corresponding to the part. In the step (F), when the component laminated shell model in which the position of the element dividing line does not coincide with the substrate laminated shell model at the mounting position of the component on the surface of the substrate laminated shell model, The distance between the intersection of the element division line of one model of the component stacking shell model and the intersection of the nearest element division line of the other model to join the intersection of the element division line of the other model A joining intermediate file is generated based on the rigidity between them. In the step (D-2), the board neutral plane calculated from the board laminated shell model and the component neutral plane calculated from the component laminated shell model are combined with a joining element equivalent to the mounting condition of the parts and the joining intermediate file. Combine to form an analytical model. In step (E), boundary conditions are given to the analysis model to calculate deformation. Note that the step (B-3) in FIG. 24 may be performed before the step (A).

  In the step (D-2), as shown in FIG. 25, the substrate neutral surface 14 of the substrate laminated shell model 11 and the component neutral surface 26 of the component laminated shell model 19 are joined to a beam element 28 as a joining element. However, when the multilayer wiring board and the component are bonded by bumps such as solder balls, the bonding element is not the beam element 28 but a solid element as shown in FIG. Even when the analysis model 29 coupled by the element 31 is used, the analysis can be performed by coupling using the joining intermediate file. In FIG. 26, the connecting portions by one bump are shown, but there are as many connecting portions by the solid elements 31 as the number of bumps.

  In addition, the component mounting board analysis program for operating the electronic computer 6 so as to execute the component mounting board analysis method of each of the above embodiments can be written and distributed on a recording medium. It can also be distributed to terminals via the Internet line, etc., and installed and operated on an electronic computer.

  27A, 27B, and 27C show specific examples of using the joining intermediate file when the joining element is the solid element 31 in each of the above embodiments. Here, the contact joints that are joined with the joints coincided in calculation using the joining intermediate file are shown separately in the drawing. Furthermore, the three-dimensional shape of the solid element 31 of the bump such as a solder ball is the cylindrical shape shown in FIG. 26 or the cylindrical shape shown in FIG. Nodes on the substrate side of the solid elements 31 are arranged concentrically.

  In FIG. 27A, the node on the part side of the solid element 31 coincides with the node on the part neutral surface 26 of the part laminated shell model 19, but the node on the board side of the solid element 31 is the board laminated shell model 11. This shows a state inconsistent with the nodes of the substrate neutral plane 14. In this case, the node on the substrate side of the solid element 31 is coupled by being equivalent to the node of the substrate neutral plane 14 of the substrate laminated shell model 11 using the bonding intermediate file.

  In FIG. 27B, the node on the board side of the solid element 31 coincides with the node of the board neutral surface 14 of the board laminated shell model 11, but the node on the part side of the solid element 31 is the part laminated shell model 19. This shows a state inconsistent with the nodes of the component neutral plane 26. In this case, the node on the component side of the solid element 31 is coupled by being equivalent to the node of the substrate neutral surface 26 of the component laminated shell model 19 using the joining intermediate file.

  FIG. 27 (c) shows that the node on the part side of the solid element 31 does not coincide with the node on the part neutral surface 26 of the part laminated shell model 19, and the node on the board side of the solid element 31 is that of the board laminated shell model 11. In this case, the node on the substrate side of the solid element 31 is replaced with the node of the substrate neutral surface 14 of the substrate laminated shell model 11 using the bonding intermediate file. The joint on the part side of the solid element 31 is equivalent to the joint on the board neutral surface 26 of the part laminated shell model 19 by using the joining intermediate file.

  If a mismatch between the node on the substrate side of the solid element 31 and the node on the substrate neutral surface 14 of the substrate laminated shell model 11 occurs, the substrate laminated shell model is based on the node on the substrate side of the solid element 31. By subdividing 11, it is possible to combine without using the joining intermediate file. Specifically, first, as shown in FIG. 28A, for each n-th layer on the uppermost surface of the multilayer wiring board, each node 32 coinciding with the node on the board side of the solid element 31 is determined. As shown in FIG. 28B, the areas other than 32 are re-divided into element division lines 33 based on the outer shape of the multilayer wiring board and the wiring pattern of each layer as shown in FIG. The area that is left undivided in FIG. 28B is further divided by the dividing line 34 to generate a single-layer model. The n-1th layer,..., The second layer, and the first layer are similarly subdivided, and the single layer model for each of the layers that has been subdivided is obtained as the thickness information of each layer of the multilayer wiring board. Is used to generate a substrate laminated shell model laminated in the shape of the multilayer wiring board, and the substrate neutral surface 14 of the substrate laminated shell model 11 completed by the re-division is used for analysis.

  Further, when a mismatch between the node on the component side of the solid element 31 and the node on the component neutral surface 26 of the component stacked shell model 19 occurs, the component stacked shell model is based on the node on the component side of the solid element 31. As in FIG. 28, each node 32 corresponding to the node on the part side of the solid element 31 is determined, and an area other than each node 32 is subdivided by an element dividing line based on the part, and each node 32 is determined. A part shell model in which each single layer model generated by further dividing the remaining area without being divided around is generated in the shape of the part is generated, and this part is completed by subdivision. By using the component neutral surface 26 of the laminated shell model 19 for the analysis, it is possible to connect without using the joining intermediate file.

  According to the present invention, a stress analysis of a plate-like body such as a multilayer wiring board or a semiconductor integrated circuit can be obtained in a short time with a small number of calculation steps. This is effective for changing and correcting the CAM data.

Flow diagram of stress analysis of multilayer wiring board based on plate-like body analysis method of the present invention Exploded view of the multilayer wiring board of the same embodiment Explanatory drawing of the material type assignment process in the single-layer model of the same embodiment Explanatory drawing of the laminated shell model in which the single-layer model of the same embodiment is laminated Illustration of the neutral plane calculated from the laminated shell model of the same embodiment Claim correspondence diagram of claim 1 Explanatory drawing of layer division of component laminated shell model Explanatory drawing of element division of component laminated shell model Illustration of subdivision of the board stacking shell model Illustration of coupling of component neutral surface and substrate neutral surface FIG. 10 is an explanatory diagram of the coupling between the component neutral surface and the substrate neutral surface, and an explanatory diagram of another embodiment when a resin-based bonding material is used in combination. Flow diagram of another embodiment of material type assignment process Explanatory drawing of FIG. Explanatory drawing in which the cell size is different after subdivision of the single layer model and before cell division Flow chart for executing the process of FIG. Claim correspondence diagram of claim 2 Claim correspondence diagram of claim 5 Claim correspondence diagram of claim 6 Claim correspondence diagram of claim 8 Claim correspondence diagram of claim 9 Claim correspondence diagram of claim 10 Explanatory drawing of the joining intermediate file of FIG. Claim correspondence diagram of claim 11 Claim correspondence diagram of claim 12 Explanatory drawing when the substrate neutral surface 14 and the component neutral surface 26 are coupled by a beam element. Explanatory drawing when substrate neutral surface 14 and component neutral surface 26 are coupled with solid elements Specific explanatory diagram in the case where the substrate neutral surface 14 and the component neutral surface 26 are coupled by solid elements Process diagram for re-dividing the substrate stacking shell model 11 based on the node on the substrate side of the solid element 31

Explanation of symbols

7 Substrate 8 Copper foil pattern 11 Laminated shell model 11A Deformed multilayer wiring board 14 Substrate neutral plane 14A Deformed neutral plane d1 Distance from upper surface of substrate laminated shell model 11 d2 Substrate neutral from lower surface of substrate laminated shell model 11 Distance to surface 14 Component laminated shell model 21 External connection terminal 26 Component neutral surface 27 Land 28 on surface of multilayer wiring board Cylindrical beam element equivalent to soldering (joining element)
29 Analytical model 30 Beam element (joint element) of quadratic prism equivalent to resin-based joint material
31 Solid elements (joint elements)

Claims (13)

When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of each layer of the multilayer wiring board and the wiring pattern of each layer, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is obtained as thickness information for each layer. (A) generating a substrate laminated shell model laminated using
(B) generating a component stacking shell model divided by element dividing lines based on the bonding position of the component to the surface of the multilayer wiring board;
A step (C) of re-dividing the mounting position of the component of the board laminated shell model with the element dividing line used when generating the component laminated shell model;
The board neutral plane calculated from the subdivided board stacking shell model and the component neutral plane calculated from the component stacking shell model are connected by a beam element or a solid element which is a joining element equivalent to the mounting condition of the component. Forming an analysis model by (D),
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land on which the component is surface-mounted, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is generated A step (A-2) of generating a substrate lamination shell model obtained by laminating using the thickness information of each layer,
(B) generating a component stacking shell model divided by element dividing lines based on the bonding position of the component to the surface of the multilayer wiring board;
An analysis model is created by combining the board neutral plane calculated from the board stacking shell model and the component neutral plane calculated from the component stacking shell model with beam elements or solid elements that are equivalent to the mounting conditions of the parts. Forming (D);
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. In the step (D) of connecting the substrate neutral surface and the component neutral surface with a beam element or solid element as a joining element to form an analysis model,
The resin-based bonding material of the resin-based bonding material area is defined as a node of the resin-based bonding material area excluding the node connected by the beam element or solid element that is the bonding element between the substrate laminated shell model and the component laminated shell model. The component mounting board analysis method according to claim 1, wherein the analysis model is calculated by joining with joint elements having equivalent mechanical strength. A component data library storing the data of the components used to analyze the physical characteristics of a component mounting board having components mounted on the surface of a multilayer wiring board,
Component data live in which a component stacking shell model in which elements are divided on the basis of the junction dividing line passing through the junction position of the component to the surface of the multilayer wiring board is recorded corresponding to each component. Rally. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines, and the single layer model for each layer is used using the thickness information of each layer. A step (A) for generating a laminated substrate shell model,
Component data in which a component stacking shell model obtained by dividing an element based on the joint division line passing through the joining position of the component to the surface of the multilayer wiring board is recorded corresponding to each component. Reading out the component stacking shell model from the library (B-2);
A step (C) of re-dividing the mounting position of the component of the board laminated shell model at an element dividing line of the component laminated shell model;
An analysis model in which a substrate neutral surface calculated from a substrate stacking shell model and the component neutral surface calculated from a component stacking shell model are connected by a beam element or a solid element which is a joining element equivalent to the mounting condition of the component. Forming a step (D);
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land on which the component is surface-mounted, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is generated A step (A-2) of generating a substrate lamination shell model obtained by laminating using the thickness information of each layer,
From a component data library in which a component stacking shell model in which elements are divided on the basis of the joint division line passing through the joint position to the surface of the multilayer wiring board is recorded corresponding to each component. A step (B-2) of reading the component laminated shell model;
An analysis model is created by combining the board neutral plane calculated from the board stacking shell model and the component neutral plane calculated from the component stacking shell model with beam elements or solid elements that are equivalent to the mounting conditions of the parts. Forming (D);
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. A component data library that accumulates the data of the component to analyze the physical characteristics of the component mounting board with the component mounted on the surface of the multilayer wiring board,
Corresponding to a component neutral surface calculated from a component stacking shell model that is divided into elements based on the external shape, internal structure of the component, and the bonding dividing line passing through the bonding position of the component to the surface of the multilayer wiring board. Recorded parts data library. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines, and the single layer model for each layer is used using the thickness information of each layer. A step (A) for generating a laminated substrate shell model,
Corresponding to the component neutral surface calculated from the component stacking shell model divided by the element dividing line based on the part dividing line passing through the joining position to the surface of the multilayer wiring board Reading out from the recorded component data library (B-3),
A step (C) of re-dividing the mounting position of the component of the board laminated shell model at an element dividing line of the component laminated shell model;
An analysis model is formed by combining the substrate neutral surface calculated from the subdivided substrate laminated shell model and the component neutral surface with a beam element or a solid element which is a joint element equivalent to the mounting condition of the component. Step (D);
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board, the wiring pattern of each layer, and the position of the land on which the component is surface-mounted, a single layer model is generated for each layer in which each layer is divided by element dividing lines, and the single layer model for each layer is generated A step (A-2) of generating a substrate lamination shell model obtained by laminating using the thickness information of each layer,
The component neutral surface calculated from the component stacking shell model divided by the element dividing line based on the outer shape of the component, the internal structure, and the bonding dividing line passing through the bonding position of the component to the surface of the multilayer wiring board, A step (B-3) of reading from the component data library recorded corresponding to the component;
A step of forming an analysis model by combining the substrate neutral surface calculated from the substrate laminated shell model and the component neutral surface with a beam element or a solid element which is a joint element equivalent to the mounting condition of the component (D) When,
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines, and the single layer model for each layer is used using the thickness information of each layer. A step (A) for generating a laminated substrate shell model,
(B) generating a component stacking shell model divided by element dividing lines based on the bonding position of the component to the surface of the multilayer wiring board;
When the component stacking shell model in which the position of the parting line does not match the board stacking shell model is joined to the mounting position of the component on the surface of the substrate stacking shell model, the board stacking shell model and the component stacking shell model Based on the distance from the intersection of the nearest element dividing line of the other model to the intersection of the nearest element dividing line of the other model and the rigidity between them A step (F) of generating a joining intermediate file;
The board neutral plane calculated from the board stacking shell model and the part neutral plane calculated from the part stacking shell model are connected to the beam element or solid element, which is a joint element equivalent to the mounting conditions of the part, using the joint intermediate file. And forming an analysis model (D-2),
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines, and the single layer model for each layer is used using the thickness information of each layer. A step (A) for generating a laminated substrate shell model,
Component data in which a component stacking shell model obtained by dividing an element based on the joint division line passing through the joining position of the component to the surface of the multilayer wiring board is recorded corresponding to each component. Reading out the component stacking shell model from the library (B-2);
When the component stacking shell model in which the position of the parting line does not match the board stacking shell model is joined to the mounting position of the component on the surface of the substrate stacking shell model, the board stacking shell model and the component stacking shell model Based on the distance from the intersection of the nearest element dividing line of the other model to the intersection of the nearest element dividing line of the other model and the rigidity between them A step (F) of generating a joining intermediate file;
The board neutral plane calculated from the board stacking shell model and the part neutral plane calculated from the part stacking shell model are connected to the beam element or solid element, which is a joint element equivalent to the mounting conditions of the part, using the joint intermediate file. And forming an analysis model (D-2),
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. When analyzing the physical characteristics of a component mounting board with components mounted on the surface of a multilayer wiring board,
Based on the outer shape of the multilayer wiring board and the wiring pattern of each layer, a single layer model for each layer is generated by dividing the inside of each layer by element dividing lines, and the single layer model for each layer is used using the thickness information of each layer. A step (A) for generating a laminated substrate shell model,
The component neutral surface calculated from the component stacking shell model divided by the element dividing line based on the outer shape of the component, the internal structure, and the bonding dividing line passing through the bonding position of the component to the surface of the multilayer wiring board, A step (B-3) of reading from the component data library recorded corresponding to the component;
When the component stacking shell model in which the position of the parting line does not match the board stacking shell model is joined to the mounting position of the component on the surface of the substrate stacking shell model, the board stacking shell model and the component stacking shell model Based on the distance from the intersection of the nearest element dividing line of the other model to the intersection of the nearest element dividing line of the other model and the rigidity between them A step (F) of generating a joining intermediate file;
The board neutral plane calculated from the board stacking shell model and the part neutral plane calculated from the part stacking shell model are connected to the beam element or solid element, which is a joint element equivalent to the mounting conditions of the part, using the joint intermediate file. And forming an analysis model (D-2),
A component mounting board analysis method including a step (E) of calculating a deformation by giving a boundary condition to the analysis model. A component mounting board analysis method according to any one of claims 1, 2, 5, 6, 8, 9, 10, 11, and 12 is executed. Analysis program for component mounting boards.

Images