1. Field of the Invention
The present invention relates to a method for manufacturing a circuit board containing a component, as well as to a circuit board containing a component.
2. Brief Description of the Related Art
Layers containing a component are manufactured, for example, when manufacturing multi-layer circuit boards or other corresponding electronic modules. In particular, the invention relates to a method for manufacturing a layer, which contains one or several components, which are connected electrically to an external circuit, or to each other, with the aid of conductor structures manufactured in the electronic module.
US Publication No. 2005/0001331 discloses a manufacturing method for circuit-board structure, in which first of all a circuit board, which comprises an insulator layer and a conductor pattern on the surface of it, is manufactured. After that, a semiconductor component is then connected to the conductor pattern of the surface of the circuit board, using a suitable flip-chip attachment method. The connection is made with the aid of contact bumps on the surface of the semiconductor component. In the method of the US publication, after attachment of the component, a patterned and unpatterned insulating-material layer is laminated on top of the circuit board and then on their surface a conductor-pattern layer.
U.S. Pat. Nos. 6,038,133 and 6,489,685, as well as US Publication No. 2002/0117743 disclose methods, in which a conductor pattern is made on the surface of a detachable membrane and a semiconductor component is attached to the conductor pattern using a flip-chip attachment method. After this, the component is surrounded with a layer of insulating material and the detachable membrane is removed.
The aforementioned U.S. Pat. No. 6,038,133 and US Publication No. 2002/0117743 also disclose a method, in which a flip-chip method is used to attach the component not to a conductor pattern, but to a unified conductor membrane, from which conductor patterns are formed in a later stage of the process. A corresponding method is also disclosed in, for example, U.S. Pat. No. 5,042,145, WO 2004/077902, WO 2004/077903, and WO 2005/020651.
In addition to the types of method referred to above, many other methods are known, by means of which circuit-board structures containing components can be manufactured. For example, the components can be first of all placed inside an insulating-material layer and connected electrically to the conductor layer only after this, as is disclosed in International Publication No. WO 2004/089048. In the method of WO 2004/089048, the component is glued onto the surface of the conductor layer and after the component has been glued an insulating-material layer is formed on, or attached to the surface of the conductor layer. After the gluing of the component, vias are also made, through which electrical contacts can be formed between the conductor layer and the component. After this, conductor patterns are formed from the conductor layer, to the surface of which the component has been glued. With the aid of the method described by the publication, it is possible to manufacture mechanically durable electronic modules, which contain embedded unpacked components. A good side of the method is also the fact that the contacts to the components can be made by growing metal, in which case the electrical properties of the contacts will be excellent.
However, the method disclosed in WO 2004/089048 differs from the conventional circuit-board manufacturing process to such an extent that its introduction to mass production will in most cases require the construction of a new manufacturing line, or at least alterations to a traditional manufacturing line. Thus the introduction of the method will also demand considerable initial investments.
The invention is intended to improve the method disclosed in WO 2004/089048, so that it can be exploited more easily also in connection with traditional circuit-board manufacturing processes.
The invention is based on first of all manufacturing an intermediate product, which contains the insulator layer of the circuit board and the components, which are attached in place inside the insulator layer, in such a way that the contact elements of the components open onto the surface of the intermediate product, or at least extend into the vicinity of the surface of the intermediate product. After this, the intermediate product is transferred to a circuit-board manufacturing line, on which a suitable number of conductor-pattern layers, and if necessary insulator layers are made on one or both sides of the intermediate product, in such a way that in the manufacture of the first conductor-pattern layer the conductor material forms an electrical contact with the contact elements of the components.
At the same time, according to the invention an alternative method is also created for manufacturing the product described in WO 2004/089048.
Considerable advantages are gained with the aid of the invention.
With the aid according to the invention, the method disclosed in WO 2004/089048 can be more easily utilized also in connection with traditional circuit-board manufacturing processes.
With the aid of the invention, an alternative method is also presented for manufacturing the product described in WO 2004/089048.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.