US-12628281-B2 - Method for producing multi-layer circuit boards

US12628281B2US 12628281 B2US12628281 B2US 12628281B2US-12628281-B2

Abstract

A method for producing multi-layer circuit boards, wherein, in an assembly method step, multiple functional layers and at least one insulating layer of a circuit board to be produced are arranged in layers between a tool lower part and a tool upper part of a multi-part tool. At least one measuring transducer is positioned between the tool upper part and the tool lower part such that the measuring transducer is in contact with at least one functional layer and/or insulating layer of the circuit board to be produced. The tool is then introduced into a thermo-compression chamber. The tool upper part and the tool lower part, along with the multiple functional layers and the at least one insulating layer and the measuring transducer provided between same, are then pressed against one another in the thermo-compression chamber and heated and measurement values are detected with the measuring transducer.

Inventors

Ulrich Rotte

Assignees

ULRICH ROTTE ANLAGENBAU UND FOERDERTECHNIK GMBH

Dates

Publication Date: 20260512
Application Date: 20240313
Priority Date: 20210914

Claims (18)

1 . A method for to produce multi-layer circuit boards, the method comprising: arranging, within an assembly method step, at least two functional layers and at least one insulation layer of a circuit board to be produced in a layered manner between a tool lower part and a tool upper part of a multi-part tool; positioning at least one measurement value sensor between the tool upper part and the tool lower part such that the measurement value sensor lies against at least one of the at least two functional layers and/or the at least one insulation layer of the circuit board to be produced; inserting, in an equipping step, the multi-part tool with the at least two functional layers and the at least one insulation layer and the at least one measurement value sensor into a thermo-compression chamber; pressing, in a production step, the tool upper part and the tool lower part against each other in the thermo-compression chamber, with the at least two functional layers, provided therebetween and the at least one insulation layer and the measurement value sensor provided between the tool upper part and the tool lower part, the tool upper part and the tool lower part being pressed together while being heated via at least a first heating plate, wherein the tool lower part is positioned on top of the first heating plate; detecting measurement values by the measurement value sensor; transferring the measurement values and/or data obtained therefrom to a production control device during the production step; and processing the measurement values and/or the data obtained therefrom by the production control device during the production step to monitor the production step and/or to control the production step in relation to a set value for a measurement variable of the measurement value sensor.
2 . The method as claimed in claim 1 , wherein the measurement values are transferred to the production control device in part wirelessly.
3 . The method as claimed in claim 2 , wherein the measurement values are transferred in a hybrid manner or in part wirelessly or in part via cables or wires.
4 . The method as claimed in claim 1 , wherein the measurement values are fed away from the multi-part tool via cables or wires.
5 . The method as claimed in claim 1 , wherein the measurement values are fed via cables or wires away from the thermo-compression chamber to the production control device provided outside the thermo-compression chamber.
6 . The method as claimed in claim 2 , wherein the measurement values are transferred wirelessly from a transmitter arranged in the thermo-compression chamber to a receiver cooperating with the transmitter.
7 . The method as claimed in claim 6 , wherein the transmitter is fluidically cooled in the thermo-compression chamber, and wherein a cooling fluid is supplied and/or discharged via at least one fluid line.
8 . The method as claimed in claim 6 , wherein the transmitter together with the multi-part tool or as part thereof is positioned and/or aligned relative to the receiver when the multi-part tool is being inserted into the thermo-compression chamber.
9 . The method as claimed in claim 1 , wherein a temperature and/or a pressure and/or a humidity level are determined as the measurement values.
10 . The method as claimed in claim 1 , wherein, during the processing of the measurement values and/or the data obtained therefrom by the production control device, the measurement values and/or the data obtained therefrom are compared with stored reference values, and wherein the set values form the basis of the comparison as reference values for the measurement variable of the measurement value sensor.
11 . The method as claimed in claim 1 , wherein a duration of the production step is determined in dependence upon the measurement values and/or the data obtained therefrom, and/or in wherein the production step is continued beyond a set value for the duration of the production step or is terminated before reaching the set value for the duration of the production step.
12 . The method as claimed in claim 1 , wherein a target temperature to which the thermo-compression chamber is heated is increased above a set value for the target temperature and/or is set differently from the set value for the target temperature in the production step in dependence upon the measurement values and/or the data obtained therefrom.
13 . The method as claimed in claim 1 , wherein a target pressure applied to the multi-part tool in the thermo-compression chamber is increased above a set value for the target pressure and/or is set differently from the set value for the target pressure in the production step in dependence upon the measurement values and/or the data obtained therefrom.
14 . The method as claimed in claim 1 , further comprising a second heating plate that is positioned on top of the tool upper part, such that during the pressing step, the tool upper part and the tool lower part are pressed and heated by both the first heating plate and the second heating plate.
15 . The method as claimed in claim 1 , wherein the measurement values are transferred wirelessly from a transmitter arranged in the thermo-compression chamber to a receiver arranged in the thermo-compression chamber, and the receiver transmits the measurement values to the production control device that is located outside of the thermos-compression chamber.
16 . The method as claimed in claim 15 , wherein the transmitter is arranged in a housing that is positioned on top of the tool lower part, and wherein the receiver is positioned outside of the housing.
17 . The method as claimed in claim 15 , further comprising a support body, wherein a first end of the support body is mounted to the first heating plate and the receiver is mounted to a second end of the support body.
18 . The method as claimed in claim 17 , wherein the transmitter is arranged in a housing, wherein the transmitter is fluidically cooled by a cooling fluid, wherein the cooling fluid is supplied and/or discharged to the housing via at least one fluid line, and wherein the second end of the support body is provided with an opening through which the at least one fluid line extends.

Description

This nonprovisional application is a continuation of International Application No. PCT/DE2022/100670, which was filed on Sep. 12, 2022, and which claims priority to German Patent Application No. 10 2021 123 685.1, which was filed in Germany on Sep. 14, 2021, and which are both herein incorporated by reference. BACKGROUND OF THE INVENTION Field of the Invention The invention relates to a method for the production of multi-layer circuit boards, wherein initially, within an assembly method step, a plurality of functional layers and at least one insulation layer of a circuit board to be produced are arranged in a layered manner between a tool lower part and a tool upper part of a multi-part tool and at least one measurement value sensor is positioned between the tool holder upper part and the tool holder lower part such that the measurement value sensor lies against at least one functional layer and/or insulation layer of the circuit board to be produced, wherein then, within an equipping method step, the tool with the plurality of functional layers and the at least one insulation layer and the measurement value sensor is inserted into a thermo-compression chamber, and wherein then, within a production method step, the tool upper part and the tool lower part with the plurality of functional layers provided therebetween and the at least one insulation layer and the measurement value sensor are pressed against each other and heated in the thermo-compression chamber, and measurement values are detected by the measurement value sensor. Description of the Background Art Multi-layer circuit boards are currently usually produced in a multi-platen heat press, wherein suitable process parameters for the operation of the multi-platen press heater are determined within experimental testing of the production process, and the subsequent mass production is carried out using the process parameters experimentally determined in this way. In order to ascertain the necessary parameters during the experimental testing, in particular copper-based functional layers and insulation layers are laid one on top of the other in an alternating manner in the tool as a preparatory step in the assembly method step. A temperature sensor as the measurement value sensor is positioned between two of these layers and a signal line is fed out of the tool. The temperature sensor thus forms a lost sensor which cannot be reused. A free end of the signal line is typically temporarily fixed to an outer side of the tool, for example by means of an adhesive strip. The equipped tool is then inserted with a multiplicity of further tools into a multi-platen heat press in the equipping method step. The tool lower part thus lies on a heating plate of the multi-platen heat press and is aligned and/or positioned relative to same. The heating plate serves as the support for the tool. The tool upper part is spaced apart from a further heating plate disposed above same, which—with the exception of the uppermost heating plate—supports a further equipped tool. Now, in order to ascertain measurement values and to be able to determine process parameters in the experimental testing, the free ends of the signal line are released from the respective tool and connected to a data storage box which is disposed with the heating plates and the tools in a thermo-compression chamber of the multi-platen heat press. The thermo-compression chamber is then closed and the heating plates are moved towards each other in a subsequent production method step in such a way that the tools are located sandwiched between two heating plates and heat the equipped tools, wherein the functional and insulation layers in the tool are connected under pressure. During this process, in particular the temperature inside the tool is measured by means of the temperature sensor. The determination of the process parameters is effected off-line within the experimental testing. During the experimental testing, the data are merely captured and collected in the data storage box. The processing and evaluation of the data are effected downstream. The measurement values ascertained during the experimental testing specifically do not serve for intervention in the on-going production method step in a controlling or regulating manner. Furthermore, by reason of the restricted space available and the temperatures of typically 100° C. or more prevailing there, the work involved in manually cabling the individual temperature sensors in the hot multi-platen heat press is laborious, time-consuming and involves a burns risk for the machine operator. In exceptional cases, the procedure described above for the case of experimental testing is also applied within the mass production of circuit boards. However, by reason of the large amount of time involved and the high costs associated therewith, this work is only carried out in exceptional cases, for example when the circuit boards to be produced are used in safety-critical a