Patent Publication Number: US-2006017133-A1

Title: Electronic part-containing elements, electronic devices and production methods

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to an electronic part-containing or built-in element used, while being buried in, for example, a wiring board, in the production of electronic devices such as semiconductor devices, to a method of producing the same, to an electronic device incorporating the electronic part-containing element of the present invention, and to a method of producing the same.  
      2. Description of the Related Art  
      In recent years, to satisfy the requirements of high performance, high degree of function, small size and decreased weight of electronic equipments and other devices, efforts have been made to improve both the constitution of the devices and the production processes concerning semiconductor devices and other electronic devices. In semiconductor devices, for example, it is a widely accepted practice to very densely mount active elements such as semiconductor elements and passive elements such as capacitors and resistors, in order to decrease the thickness, size and weight of the devices.  
      For example, Japanese Unexamined Patent Publication (Kokai) No. 2002-261449 discloses a part-containing module having a multi-layer wiring structure and incorporating active elements and passive elements therein. Referring to  FIG. 1 , the part-containing module has a core layer  105 . The core layer  105  includes an electrically insulating layer  102  made of a composite material of an inorganic filler and a thermosetting resin, and a wiring pattern  100 . On the wiring pattern  100 , there are mounted a bare semiconductor chip (active part)  101  and a chip part (passive part)  104 . The wiring patterns  100  are electrically connected together through inner viaholes  103 . Reference numerals  106 ,  107 , and  108  denote electrically insulating layers, inner viaholes and wiring patterns, respectively.  
      In the above part-containing module, however, ready-made active parts and passive parts are buried therein causing a problem of an increased thickness of the layer in which parts having large thicknesses are buried. In practice, the obtained part-containing module has a thickness of about 1000 μm hindering an effort to decrease the thickness of the packages (generally, of the order of about 100 to 1,000 μm) that has been demanded in recent years.  
      Further, Japanese Unexamined Patent Publication (Kokai) No. 2002-164467 discloses a circuit block body formed on a mother board so as to be peeled off and a method of its production.  FIG. 2  illustrates a state after a circuit block body  202  is separated from a mother board  201 . The circuit block body  202  can be produced through a step of forming a peeling layer  206  on the main flat surface of the mother board  201  made of an Si board  205 , a step of forming insulating layers  207 ,  209  and  214  on the peeling layer  206 , a step of forming wiring layers  208 ,  211  and  216  on the respective insulating layers, and a step of separating the circuit block body  202  from the mother board  201  via the peeling layer  206 . The circuit block body  202  has a resistor  212 , a capacitor  213  and an inductor  217 , which are passive elements, buried therein, during the process of production, by relying upon a thin-film technology. The circuit block body  202  is capable of mounting a semiconductor chip (not shown) on the surface thereof. Reference numerals  210  and  215  denote viaholes.  
      However, the following problems exist when the passive elements are fabricated between the layers and in the core during the process of producing the semiconductor device according to the above-mentioned method.  
      1) The production process can be carried out only under low-temperature conditions and cannot be adapted to a high-temperature production process of not lower than 200° C. that has been demanded in recent years.  
      2) The passive elements must be formed by using the whole surface of the motherboard to increase the cost of production due to the use of an expensive material for forming the passive elements.  
      3) Each passive element is formed through a different process and, hence, it is difficult to form a circuit (an LCR circuit) mounting, for example, an inductor, a capacitor and a resistor in one build-up layer.  
     SUMMARY OF THE INVENTION  
      The present invention is directed to solve the above-mentioned prior art problems, and has an object to provide an electronic device which highly densely mounts active elements such as semiconductor elements and passive elements such as resistors and capacitors making it possible to decrease the thickness, size and weight of the device, contributing to decreasing the thickness of the package, permitting a low-temperature production process to be applied, and making it possible to form an LCR circuit in one build-up layer without using the whole surface of the substrate for forming the passive elements, as well as a novel electronic part-containing element useful for the manufacture of the electronic devices.  
      It is further an object of the present invention to provide a method useful for the production of an electronic part-containing element and an electronic device.  
      The above and other objects of the present invention will be easily understood from the following detailed description of the present invention.  
      According to one aspect of the present invention, there is provided an electronic part-containing or -built in element used by being incorporated in an electronic device, in which the electronic part-containing element comprises a support member which does not take part in the constitution of the electronic device but is removed in the process of producing the electronic device, and a circuit module supported by the support member, and in which the circuit module contains one or more electronic parts each in the form of a thin film therein and comprises connection terminals for the electronic parts at least on the surface thereof that comes into contact with the support member.  
      According to another aspect of the present invention, there is provided a method of producing an electronic part-containing element used by being incorporated in an electronic device, which comprises: 
          providing a support member which does not take part in the constitution of the electronic device but is removed in the process of producing the electronic device; and     forming a circuit module on the support member, in which one or more electronic parts are fabricated by utilizing a thin film-forming technology in the circuit module while the circuit module is being formed, and connection terminals for the electronic parts are formed at least on the surface of the circuit module that comes into contact with the support member.        

      According to a further aspect of the present invention, there is provided an electronic device incorporating one or more electronic parts, each in the form of a thin film, wherein the electronic part is a part of an electronic part-containing circuit module that is formed by incorporating, in any portion of the electronic device, an electronic part-containing element which comprises a circuit module containing the electronic part therein and a support member supporting the circuit module, and has connection terminals for the electronic parts at least on the surface of the circuit module that comes into contact with the support member and, thereafter, by removing the support member in the step of producing the electronic device.  
      According to a still further aspect of the present invention, there is provided a method of producing an electronic device incorporating one or more electronic parts each in the form of a thin film, comprising: 
          incorporating, in any portion of the electronic device, an electronic part-containing element which comprises a circuit module containing the electronic part therein and a support member supporting the circuit module, and has connection terminals for the electronic parts at least on the surface of the circuit module that comes into contact with the support member; and     providing an electronic part-containing circuit module by removing the support member in the process of producing the electronic device.        

      As will be appreciated from the following detailed description of the present invention, the present invention does not rely upon the widely used conventional method of successively fabricating the electronic parts, i.e., active elements such as semiconductor elements and passive elements such as resistors and capacitors in producing the electronic device. Instead, the present invention allows production of an electronic part-containing element of the unit type, into which the above parts have been incorporated already, by relying on a separate production process and incorporates the electronic part-containing element in any stage in a process of producing an electronic device, achieving various distinguished effects that could not be expected from the conventional technology.  
      For example, by using the electronic part-containing element of the unit type, it is possible to highly densely mount active elements such as semiconductor elements and passive elements such as resistors and capacitors, making it possible to decrease the thickness, size and weight of the electronic device. When practically used, further, the support member has been removed from the electronic part-containing element (functional portions only are selectively used) making it possible to reduce the thickness of the electronic devices.  
      The electronic part-containing element of the unit type can be produced in advance and preserved, offering such an advantage that they can be readily offered as required. From the side of the user, further, important portions in the process for producing the electronic device can be shifted to the ready-made electronic part-containing element, offering advantages of decreasing the areas required for the production lines and for the production site and decreasing the cost of production.  
      Further, the electronic part-containing element is produced by a separate process making it possible to eliminate the waste in the material that is used and to decrease the cost of production. Besides, as the electronic parts need not be in-site buried, parts having a variety of functions can be selected to complete the electronic part-containing element. For example, application of a material having a high dielectric constant that requires a high-temperature processing and mounting of the LCR composite circuit can be carried out during the process for producing the electronic part-containing element, instead of the in-site application and mounting, it becomes possible to widen a variation of the process for producing the electronic devices. Application of the low-temperature production process also helps to widen an application width for producing the electronic devices.  
      Moreover, as the electronic parts have been buried already in the electronic part-containing element, the electrically conductive viaholes for electric conduction and the through electrodes can be easily provided for the electronic parts at the time of producing the electronic device.  
      By using the electronic part-containing element of the unit type, further, there is no need to use the whole surface of the substrate for forming the individual electronic parts, and the LCR circuit can be formed in one build-up layer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a sectional view illustrating a conventional part-containing module;  
       FIG. 2  is a sectional view illustrating a conventional circuit block body;  
       FIG. 3  is a sectional view illustrating a preferred embodiment of an electronic part-containing element according to the present invention;  
       FIG. 4  is a sectional view illustrating another preferred embodiment of the electronic part-containing element according to the present invention;  
       FIG. 5  is a sectional view illustrating a further preferred embodiment of the electronic part-containing element according to the present invention;  
       FIGS. 6A  to  6 F are sectional views illustrating, in sequence, a preferred method of producing the electronic part-containing element according to the present invention;  
       FIG. 7  is a sectional view illustrating a preferred embodiment of an electronic device according to the present invention;  
       FIG. 8  is a sectional view illustrating another preferred embodiment of the electronic device according to the present invention;  
       FIG. 9  is a sectional view illustrating a further preferred embodiment of the electronic device according to the present invention;  
       FIG. 10  is a sectional view illustrating a still further preferred embodiment of the electronic device according to the present invention;  
       FIG. 11  is a sectional view illustrating a yet further preferred embodiment of the electronic device according to the present invention;  
       FIGS. 12A  to  12 E are sectional views illustrating, in sequence, a method of producing an electronic device by using the electronic part-containing element of the present invention;  
       FIGS. 13A  to  13 G are sectional views illustrating, in sequence, another method of producing the electronic device by using the electronic part-containing element of the present invention;  
       FIGS. 14A  to  14 G are sectional views illustrating, in sequence, a further method of producing the electronic device by using the electronic part-containing element of the present invention; and  
       FIGS. 15A  to  15 E are sectional views illustrating, in sequence, a method of producing the electronic device by using the electronic part-containing element of  FIG. 5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The electronic part-containing element, the electronic device and their production methods according to the present invention can be advantageously carried out in a variety of embodiments. The present invention will now be described with reference to representative embodiments to which the invention is in no way limited.  
      The present invention, first, resides in an electronic part-containing element that is used by being incorporated in an electronic device. Here, the “electronic part” encompasses a variety of parts usually used in the field of electronic equipment and, as required, may encompass any other parts typically, however, representing active elements such as semiconductor elements like ICs, LSIs and passive elements like inductors (Ls), capacitors (Cs) and resistors (Rs). In the electronic part-containing element, the active element and the passive element may be used alone, or two or more kinds of these elements may be used in any combination.  
      Further, when used in the specification of this application, the term “electronic device” encompasses an apparatus, device, equipment and the like having at least one kind of the above-mentioned electronic parts in any portion thereof. That is, the electronic device of the present invention contains at least one electronic part-containing element of the invention in a state from which the support member has been removed and, though arbitrary, contains one or more additional electronic parts like those described above.  
      Desirably, the electronic part-containing element can be incorporated in a layer such as a core layer or a build-up layer in the electronic device. As the electronic part-containing element has a thickness (inclusive of the thickness of the electrodes), after the support member has been removed therefrom, of usually about not larger than 50 μm and generally in the range of about 10 to 50 μm, it can contribute to decreasing the thickness of the electronic device. As required, further, the electronic part-containing elements may be incorporated, as two or more kinds in parallel, in one layer of the electronic device or may, further, be incorporated simultaneously in any of two or more layers when the electronic device has a multi-layer structure. Though not necessarily limited to those described below, suitable electronic devices comprise wiring boards inclusive of multi-layer wiring boards and build-up wiring boards, semiconductor devices, semiconductor packages and the like.  
      The electronic part-containing element according to the present invention comprises, at least: 
          (1) a support member which does not take part in the constitution of the electronic device but is removed in the step of producing the electronic device; and     (2) a circuit module supported by the support member.        

      In the electronic part-containing element of the present invention, the support member is used for temporarily supporting the sheet-like circuit module and is, desirably, made of an insulating material. Further, by taking into consideration the fact that the support member does not take part in the constitution of the electronic device but is removed in the step of producing the electronic device, it is desired that the support member is made of a material that can be easily removed in the step of producing the electronic device. Usually, it is desired to form the support member by using an inorganic or organic insulating material that can be removed by polishing or the like. Though not limited to those described below, the support member suited for putting the invention into practice includes inorganic material boards such as a silicon board (desirably having an SiO 2  coating), a ceramic board and a glass board, as well as organic resin boards such as a glass epoxy resin board, a polyimide resin board and a phenol resin board. The thickness of the support member can vary over a wide range depending upon the constitutions of the electronic part-containing element and the electronic device and upon the production conditions, but is, usually, in a range of about 100 to 1,000 μm.  
      The circuit module is desirably in the form of a sheet, and contains therein at least one electronic part in the form of a thin film. The electronic parts are, as described above, active elements such as semiconductor elements, and passive elements such as inductors (inductor wirings), capacitors and resistors. In the practice of the invention, desirably, a passive element is used as the electronic part. The passive element may be used alone, or two or more kinds of passive elements may be used in a composite form like an LCR circuit. In the case of the present invention, desirably, two or more kinds of passive elements can be arranged in parallel in one layer in the electronic part-containing element.  
      Desirably, further, the electronic part is incorporated in the circuit module in the form of a thin-film part. The electronic part that is formed and used in the form of a thin film is effective in decreasing the thickness, size and weight of the electronic device. Basically, the thin-film part can be formed by relying, basically, upon a thin film-forming technology that has heretofore been widely used, such as plating, electrodeposition, sputtering, vacuum evaporation, coating or lamination.  
      The circuit module has, in addition to the electronic part, connection terminals for connecting the electronic part to the electronic parts outside of the circuit module, to the wiring pattern layer (wiring circuit) or to the connection terminals. The connection terminals are usually formed by using a conducting metal such as copper or aluminum. For connecting the electronic part to the external unit, the connection terminals are at least arranged on the surface which is the main surface of the circuit module that comes in contact with the support member. When the connection terminals are arranged on the surface of the circuit module of only the side of the support member, the other surface of the circuit module is usually covered with an insulating material. When necessary, the circuit module has the connection terminals arranged on both surfaces thereof, i.e., on the first surface of the circuit module on the side of the support member and on the second surface on the side opposite to the first surface that comes in contact with the support member.  
      The circuit module can further possess through electrodes formed therein. Upon incorporating through electrodes in the circuit module, no detouring wiring is required. As a result of shortening the wiring, therefore, the characteristics can be improved and the cost of production can be decreased.  
      The circuit module can further have any constituent components necessary for forming the circuit module or the electronic device in addition to having the electronic parts, connection terminals and through electrodes. Suitable constituent components may include, for example, wiring circuits and electrodes. These constituent components, too, can be formed in any pattern by using a conducting metal such as copper or the like. The electrodes may be utilized as the connection terminals.  
      In the circuit module, further, the electronic parts and the connection terminals are usually isolated from each other relying on any insulating technology, and it is particularly recommended to apply an insulating layer. To form the insulating layer, there may be applied an insulating material such as a polyimide resin or an epoxy resin, or an insulating film of such a resin may be laminated in combination with the incorporation of the electronic parts and the connection terminals.  
      As required, the electronic part-containing element can possess additional layers in addition to the support member and the circuit module. For example, when the electronic part in the electronic part-containing element requires a higher precision, the support member and the circuit module are not directly joined together but, instead, an etching-resistant barrier layer and an etch-out layer are successively formed on the surface of the circuit module that comes in contact with the support member. For example, the barrier layer can be formed by using any etching-resistant metal material such as chromium capable of protecting the underlying circuit module from the etching at the time of removing the upper etch-out layer by etching. The thickness of the barrier layer can be varied over a wide range but is, usually, about 0.01 to 1 μm. The etch-out layer can be easily formed by using a metal material that can be etched out, such as copper or nickel. The thickness of the etch-out layer can be varied over a wide range but is, usually, about 0.1 to 10 μm.  
      Second, the present invention resides in a method of producing an electronic part-containing element of the invention that is used by being incorporated in the electronic device described above.  
      The method of producing an electronic part-containing element of the invention can be carried out in a variety of ways and, preferably, through the steps of: 
          (1) forming a support member which does not take part in the constitution of the electronic device but is removed in the step of producing the electronic device; and     (2) forming a circuit module on the support member.        

      In the method of the present invention, the support member is formed by forming an insulating board such as a silicon board maintaining a desired thickness. The surfaces of the support member that is formed can receive, as required, a chemical treatment or a mechanical treatment. When, for example, the electrodes are formed on the support member by plating copper, nonelectrolytic copper plating may be applied to the surfaces of the support member to facilitate the copper plating.  
      After the support member is formed, the circuit module of the constitution described above is fabricated on one surface thereof by any method. In fabricating the circuit module, it is desired that at least one electronic part is formed therein relying upon the thin film-forming technology. Here, further, it is desired that at least the connection terminals for the electronic part are formed on the surface of the circuit module that comes in contact with the support member.  
      The method of producing the electronic part-containing element will be further described. In the case of a composite circuit having passive elements which are an inductor, a capacitor and a resistor, for example, the electronic part-containing element can be advantageously produced through the procedure described below.  
      First, an inductor is formed on an insulating board formed as the support member. The inductor is usually formed simultaneously with the wiring circuits and electrodes that are formed on the same plane and can, hence, be advantageously formed by utilizing ordinary wiring-forming technology. For instance, the inductor comprising a copper wiring or an aluminum wiring is formed by applying a photoresist maintaining a predetermined thickness onto the insulating board, patterning the resist film by the photolithographic method to form a resist pattern having openings at portions where the inductors and electrodes are to be formed, filling copper or aluminum in the openings portions by plating. Upon peeling and removing the used resist pattern, the inductors and wirings are completed on the insulating board.  
      Next, on the insulating board on which the inductor is fabricated, there is formed a capacitor at a portion avoiding the inductor. The capacitor is constituted by a dielectric layer and electrodes (upper electrode and lower electrode) holding it. The dielectric layer of the capacitor can be formed by using various dielectrics, depending upon the constitution of the capacitor, by relying upon various film-forming methods. When the capacitor is formed by using such a dielectric as STO, BST or BTO, there can be employed sputtering, CVD or sol-gel method. Further, when the capacitor is to be formed by using such a dielectric as Ta 2 O 5  or Al 2 O 3 , there can be used anodic oxidation such as of Ta or Al. Further, when the capacitor is to be formed by using a resin material containing such a ferroelectric filler as BTO filler or the like, there can be used lamination, dispensing, electrodeposition and coating. The thickness of the dielectric layer of the capacitor can be varied over a wide range but is, usually, in a range of about 0.01 to 10 μm. Further, the electrodes holding the dielectric layer can be formed by using an electrically conducting metal such as copper like the inductor wiring. The thickness of the electrodes can be varied over a wide range but is, usually, in a range of about 1 to 10 μm.  
      After the capacitor is formed as described above, a resistor is formed on a portion that is remaining on the insulating board. The resistor can be formed by using various resistance material depending upon the constitution of the resistor by using various film-forming method. When the resistor is to be formed from such a resistance material as TaN or Pt, there can be used sputtering, CVD or sol-gel method. When the resistor is to be formed by using a carbon resistance material, there can be used vacuum evaporation. Further, when the resistor is to be formed by using a resin material such as a carbon paste, there can be used lamination, dispensing, electrodeposition and coating. Further, when the resistor is formed by using a thin nickel film, there can be used, for example, a nonelectrolytic nickel-plating solution. The thickness of the resistor can be varied over a wide range but is, usually, in a range of about 1 to 10 μm.  
      After the composite circuit of the inductor, capacitor and resistor is formed as described above, an insulating layer is formed on the uppermost layer of the resulting electronic part-containing element. The insulating layer can be formed by using a method that is generally used for the production of electronic devices. The insulating layer can be formed by using such an insulating resin material as polyimide resin or epoxy resin by relying upon lamination, press-forming or coating. Or, the insulating layer can be formed by using such an inorganic insulating material as SiO 2 , Al 2 O 3 , Ta 2 O 3 , SiN or AlN by relying upon sputtering or CVD. The thickness of the resistor can be varied over a wide range but is, usually, in a range of about 0.01 to 1 μm.  
      Third, the present invention resides in an electronic device incorporating at least one electronic part in the form of a thin film. Here, the terms “electronic part” and “electronic device” are as defined above.  
      The electronic device of the present invention at least comprises an electronic part-containing element of the invention. That is, at least one electronic part is in the electronic part-containing element of the invention comprising a circuit module containing the electronic part therein, and a support member supporting the circuit module, and having connection terminals for the electronic part at least on the surface of the circuit module that comes in contact with the support member. In the electronic device of the present invention, the electronic part-containing element is incorporated in any portion of the electronic device and, thereafter, the support member only is separated and removed from the circuit module. The electronic device of the invention incorporates, at any position therein, an electronic part originated from the electronic part-containing element, as well as an electronic part necessary for constituting the electronic device depending upon the constitution of the electronic device, such as active element, passive element, or any other part or wiring circuit, electrodes conducting viaholes or external connection terminals. For example, the electronic part can be electrically connected to a conducting pattern such as a wiring circuit or electrodes through the conducting viaholes.  
      The circuit module incorporated in the electric device of the present invention is produced together with the support member which temporarily supports it but is removed from the circuit module during the step of producing the electronic device desirably based upon the method described above through a process separate from the process for producing the electronic device. Therefore, the circuit module produced and incorporated on the site through the process for producing the electronic device lies outside the scope of the present invention.  
      As described above, the electronic device of the present invention can assume various constitutions and forms. In the practice of the invention, for instance, the electronic part-containing circuit module separated from the electronic part-containing element of the present invention can be incorporated as one member of the wiring board that constitutes the electronic device. When the wiring board is the multi-layer wiring board, the electronic part-containing circuit module can be incorporated in the uppermost layer or the core layer of the multi-layer wiring board or in both the uppermost layer and the core layer. The uppermost layer and the core layer may, respectively, incorporate therein the electronic part-containing circuit module alone or may incorporate therein two or more kinds of electronic part-containing circuit modules in combination.  
      In incorporating the electronic part-containing circuit module in the multi-layer wiring board or in other electronic devices, various methods can be used. At a given timing during the production of the electronic device, for instance, the electronic part-containing element (circuit module side) of the invention may be fixed to the member (e.g., core layer, build-up layer, etc., hereinafter also referred to as “underlying layer”) that has been formed already for constituting the electronic device and, immediately thereafter or after a step in a subsequent stage, the support member that becomes an obstacle to the electronic device is removed. According to another method, there is formed a board for temporary mounting such as a rigid board that can be removed in a subsequent step, the electronic part-containing element (circuit module side) of the invention is fixed onto the rigid board, and a wiring circuit and an insulating layer necessary for completing the electronic device are successively laminated thereon to incorporate the electronic part. Here, the support member of the electronic part-containing element can be removed in any stage in the process for producing the electronic device, and the board for temporary mounting, too, can be removed in any state in the process for producing the electronic device.  
      The electronic part-containing element can be fixed to the underlying layer or to the board for temporary mounting based on various methods. Generally, the electronic part-containing element can be advantageously fixed via a fixing member such as a die-attachment film or a burying resin or a fixing member such as a double-sided tape. As required, the electronic part-containing element can be fixed by using a die-bonding method which is generally employed for the production of electronic devices instead of using the fixing material.  
      Fourth, the present invention resides in a method of producing an electronic device of the invention incorporating at least one electronic part in the form of a thin film.  
      The method of producing the electronic device according to the present invention can be carried out in various ways, and is preferably carried out according to a method which comprises: 
          (1) incorporating, in any portion of the electronic device, an electronic part-containing element which includes a circuit module containing the electronic part therein and a support member supporting the circuit module, and has at least connection terminals for the electronic part formed on the surface of the circuit module that comes in contact with the support member; and     (2) providing an electronic part-containing circuit module by removing the support member in the step of producing the electronic device.        

      In the practice of the method of the present invention, the electronic part-containing element used in the step (1) is advantageously produced by the method which comprises the steps of: 
          forming a support member which does not take part in the constitution of the electronic device but is removed in the step of producing the electronic device; and     forming a circuit module on the support member in which at least one electronic part is fabricated by utilizing a thin film-forming technology in the circuit module while the circuit module is being formed, and connection terminals for the electronic part are formed at least on the surface of the circuit module that comes in contact with the support member.        

      The constitution of the electronic part-containing element, the support member used therein and the electronic part are as described above in detail.  
      In the method of producing the electronic part-containing element, the steps of forming the support member and of forming the circuit module are usually conducted successively. As required, however, one or more additional steps may be included after the support member is formed and, thereafter, the circuit module may be formed. For example, when a high degree of precision is required for the part, an etch-out layer and a barrier layer may be formed successively on the support member that is formed as described earlier. The etch-out layer and the barrier layer are temporarily used like the support member, and must be removed in any stage in the process for producing the electronic device.  
      According to the method of the present invention, the electronic part-containing circuit module is provided by removing the support member in the step of producing the electronic device that has been fabricated in the preceding steps. The step of removing the support member can be carried out in any stage in the process for producing the electronic device after the electronic part-containing element has been formed but is, generally, carried out immediately after the formation of the electronic part-containing element or after the electronic part-containing element is sealed with an insulating resin. That is, after the electronic part-containing element is fixed to the substrate (which in this invention is called underlying layer or the board for temporary mounting, but which, as required, may be any other constituent member) in a manner that the support member is exposed upward, the electronic device is completed through a subsequent series of processing step and machining step, and the support member is removed in any stage of the processing step or machining step for completing the electronic device.  
      Reverting to the step (1), the electronic part-containing element can be advantageously incorporated in any portion of the electronic device in various ways.  
      As described above, for example, the electronic part-containing element is fixed on the circuit module side thereof to the underlying layer (e.g., core layer, build-up layer, etc.) of the electronic device that has been formed already via, desirably, a fixing material, and a wiring circuit and an insulating layer necessary for completing the electronic device are successively formed thereon, and the electronic part is incorporated.  
      Concretely, for example, a wiring board mounting a semiconductor element as an electronic device is presumed here and, the electronic part-containing circuit module is incorporated as a member of the wiring board at the time of forming the wiring board. When the wiring board is a multi-layer wiring board, the electronic part-containing circuit module is incorporated in the uppermost layer or the core layer of the multi-layer wiring board. Further, in order to electrically connect the electronic part to the conducting pattern such as wiring circuit or electrodes, there may be utilized conducting viaholes formed by filling the through holes with a conducting metal.  
      According to an alternative method, there is formed a board for temporary mounting, such as a rigid board and, thereafter, the electronic part-containing element (circuit module side) is fixed onto the rigid substrate via a fixing material, a wiring circuit and an insulating layer necessary for completing the electronic device is successively laminated thereon, and an electronic part is incorporated. The electronic part may be mounted on the electronic device that is completed relying on a flip-chip method or a wiring-bonding method.  
     EXAMPLES  
      Next, examples of the present invention will now be described with reference to the accompanying drawings. It should be noted that the present invention is not limited to these examples only.  
       FIG. 3  is a sectional view illustrating a preferred embodiment of the electronic part-containing element of the present invention. The electronic part-containing element  10  comprises a support member  11  and a sheet-like circuit module  12  supported thereby. The support member  11  is removed in the step of producing an electronic device. A glass board is used in this embodiment. The circuit module  12  includes a composite circuit (LCR circuit) of a spiral inductor  5 , a capacitor  6  and a resistor  7 . The LCR circuit is in the form of a thin film as shown and contributes to decreasing the size of the device. Of the surfaces of the circuit module  12 , the surface that comes in contact with the support member  11  is provided with a connection terminal (lower electrode)  15 .  
      In the illustrated electronic part-containing element  10 , the inductor  5  and the lower electrode  15  are the copper wirings formed by laminating and patterning a copper foil. The capacitor (dielectric layer)  6  comprises a Ta 2 O 5  formed by the anodic oxidation of tantalum (Ta). The resistor  7  is a sputtered film of TaN. The inductor  5 , capacitor  6  and resistor  7  are covered with an insulating film  8  of an epoxy resin.  
       FIG. 4  is a sectional view illustrating another preferred embodiment of the electronic part-containing element of the present invention. Like that of  FIG. 3 , the electronic part-containing element  10  comprises a support member  11  of a glass board, and a sheet-like circuit module  12  supported thereby. The circuit module  12  includes a composite circuit (LCR circuit) of a spiral inductor  5 , a capacitor  6  and a resistor  7 . The circuit module  12  has a connection terminal (lower electrode)  15  on the surface thereof that comes in contact with the support member  11 , and has a connection terminal (upper electrode)  25  on the upper surface thereof.  
      In the illustrated electronic part-containing element  10 , the inductor  5  and the lower electrode  15  are the copper wirings formed by laminating and patterning a copper foil. The capacitor (dielectric layer)  6  comprises a Ta 2 O 5  formed by the anodic oxidation of tantalum (Ta). The upper electrode  25  is the copper wiring formed by plating copper. The resistor  7  is a sputtered film of TaN. The inductor  5 , capacitor  6  and resistor  7  are covered with an insulating film  8  of an epoxy resin.  
       FIG. 5  is a sectional view illustrating another preferred embodiment of the electronic part-containing element according to the present invention. Like those of  FIGS. 3 and 4 , the electronic part-containing element  10  comprises a support member  11  of a glass board, and a sheet-like circuit module  12  supported thereby. The circuit module  12  includes a composite circuit (LCR circuit) of a spiral inductor  5 , a capacitor  6  and a resistor  7 . The circuit module  12  has a connection terminal (lower electrode)  15  on the surface thereof that comes in contact with the support member  11 , and has a connection terminal (upper electrode)  25  on the upper surface thereof. Between the support member  11  and the circuit module  12 , there are provided a barrier layer  13 , which is a thin chromium layer formed by sputtering, and an etch-out layer  14  formed by plating copper.  
      In the illustrated electronic part-containing element  10 , the inductor  5  and the lower electrode  15  are the copper wirings formed by laminating and patterning a copper foil. The capacitor (dielectric layer)  6  comprises a Ta 2 O 5  formed by the anodic oxidation of tantalum (Ta). The upper electrode  25  is the copper wiring formed by plating copper. The resistor  7  is a sputtered film of TaN. The resistor  7  is covered with an insulating layer  19  of an epoxy resin.  
       FIGS. 6A  to  6 F are sectional views illustrating, successively, a preferred method of producing the electronic part-containing element of the present invention. As will be understood, the illustrated electronic part-containing element  10  has a structure similar to that of the electronic part-containing element  10  of  FIG. 5  but has neither the barrier layer nor the etch-out layer between the support member  11  and the circuit module  12 .  
      First, as shown in  FIG. 6A , a spiral inductor (wiring)  5  is formed on a glass board  11  formed as a support member. The inductor  5  can be formed by forming a copper foil on the surface of the glass board  11 , followed by etching. Simultaneously with this, there are formed other wiring circuit and a lower electrode  15  for the capacitor on the same plane. The inductor  5  may be formed by forming a conducting layer relying upon the nonelectrolytic plating of copper and electrolytic plating of copper instead of forming the copper foil, followed by etching.  
      Next, to form a dielectric layer of the capacitor, a Ta layer  16  is formed on the glass board  11  on which the inductor  5  has been fabricated, as shown in  FIG. 6B . The Ta layer  16  can be deposited as a thin film by sputtering Ta. The Ta layer  16  is anodically oxidized by a conventional method so as to be converted into a dielectric (Ta 2 O 5 ).  
      After the dielectric (Ta 2 O 5 ) is formed, the dielectric layer  6  of Ta 2 O 5  is etched in the presence of a resist mask  18  as shown in  FIG. 6C , to remove unnecessary portions (portions other than the capacitor). After the resist mask  18  is peeled and removed, there is exposed the dielectric layer  6  which is a part of the capacitor.  
      After the capacitor is formed as described above, a resistor  7  is formed as shown in  FIG. 6D . The resistor  7  can be formed by, for example, sputtering TaN. Through a series of these steps, a composite circuit of the inductor, capacitor and resistor is formed on the glass board.  
      Thereafter, to protect the element that is formed, an insulating layer  19  is formed on the inductor  5  and the resistor  7  as shown in  FIG. 6E . The insulating layer  19  can be formed by, for example, laminating the epoxy resin.  
      Finally, as shown in  FIG. 6F , the upper electrode for completing the capacitor  6  is formed by plating copper. As shown, further, an opening is formed in the insulating layer  19  so as to reach the wiring such as the inductor  5 , copper is plated so as to fill the opening, and copper wiring is also formed simultaneously by plating with copper.  
       FIG. 7  is a sectional view illustrating a preferred embodiment of an electronic device according to the present invention. A build-up wiring board  20  illustrated includes a core layer  21  of a composite insulating resin, and build-up wiring layers  22  formed by plating copper on both surfaces thereof via an insulating layer of an insulating resin. The upper and lower wiring layers  22  are electrically connected together through conducting viaholes  23  formed by filling the through holes with copper that is plated as shown. In the case of the shown build-up wiring board  20 , a circuit module (electronic part-containing element from which the support member has been removed)  12  of the invention is fabricated on one surface of the core layer  21  via a fixing material  9  which is a die-attachment film. The circuit module  12  has a thickness which is as thin as about 50 μm and is incorporated in one build-up wiring layer as shown. The shown build-up wiring board  20  has an insulating layer  26  in the form of a pattern as the uppermost layer thereof. Though not shown, a semiconductor element such as an LSI chip, a passive element such as a chip capacitor and any other electronic part can be mounted on the uppermost layer of the build-up wiring board  20  relying upon the flip-chip connection method or the wire-bonding method. Or, the shown build-up wiring board  20  can be mounted on the other wiring board via solder balls or the like.  
       FIG. 8  is a sectional view illustrating another preferred embodiment of the electronic device according to the present invention. The illustrated build-up wiring board  20  includes build-up wiring layers  22  formed by plating copper via an insulating layer of an insulating resin. In the case of the shown build-up wiring board  20 , a circuit module (electronic part-containing element from which the support member has been removed)  12  of the invention is fabricated in the uppermost layer. The shown circuit module  12  has a through electrode  17  formed by plating copper to penetrate therethrough. The through electrode  17  does not require the formation of the detour wiring and makes it possible to shorten the wiring and to improve the characteristics. Further, the circuit module  12  has a thickness which is as very thin as about 50 μm and is incorporated in one build-up wiring layer as shown. The illustrated build-up wiring board  20  has an insulating layer  26  in the form of a pattern as the uppermost layer thereof. Though not shown, a semiconductor element such as an LSI chip, a passive element such as a chip capacitor and any other electronic part can be mounted on the circuit module  12  contained in the build-up wiring board  20  relying upon the flip-chip connection. Further, the shown build-up wiring board  20  can be mounted on the other wiring board via solder balls or the like.  
       FIG. 9  is a sectional view illustrating a further preferred embodiment of the electronic device according to the present invention. The illustrated build-up wiring board  20  includes a core layer  21  of a composite insulating resin, and build-up wiring layers  22  formed by plating copper on both surfaces thereof via an insulating layer of an insulating resin. The upper and lower wiring layers  22  are electrically connected together through conducting viaholes  23  formed by filling the through holes with copper that is plated as shown. In the case of the shown build-up wiring board  20 , a circuit module (electronic part-containing element from which the support member has been removed)  12  of the invention is fabricated in the core layer  21 . In the illustrated embodiment, one circuit module (thickness of about 50 μm) is fabricated nearly at the central portion of the core layer  21  but it may be fabricated in other portion as required or it may be fabricated in a number of two or more. The shown build-up wiring board  20  has an insulating layer  26  in the form of a pattern as the uppermost layer thereof. Though not shown, a semiconductor element such as an LSI chip, a passive element such as a chip capacitor and any other electronic part can be mounted on the uppermost layer of the build-up wiring board  20  relying upon the flip-chip connection or the wire-bonding method. Or, the shown build-up wiring board  20  can be mounted on the other wiring board via solder balls or the like.  
       FIG. 10  is a sectional view illustrating a further preferred embodiment of the electronic device according to the present invention. The illustrated build-up wiring board  20  is constituted in the same manner as the build-up wiring board  20  of  FIG. 9 . In the case of the build-up wiring board  20  of this embodiment, the circuit module  12  contained in the core layer  21  further has through-type electrodes  17 . The through-type electrodes  17  provided in the circuit module  12  make it possible to omit the detouring wiring, shorten the wiring and to improve the characteristics, which are the additional effects.  
       FIG. 11  is a sectional view illustrating a further preferred embodiment of the electronic device according to the present invention. The illustrated build-up wiring board  20  is constituted in the same manner as the build-up wiring board  20  of  FIG. 10 . In the case of the build-up wiring board  20  of this embodiment, two circuit modules  12  each having the through electrode  17  are contained in the core layer  21  and, besides, another two circuit modules  12  are fabricated in one build-up wiring layer. Upon containing a total of four circuit modules  12 , the build-up wiring board  20  exhibits further enhanced characteristics.  
      The electronic devices (build-up wiring boards) of the invention shown in FIGS.  7  to  11  can be produced by burying the electronic circuit-containing element and, particularly, the circuit module of the present invention, by various methods.  
       FIGS. 12A  to  12 E are sectional views illustrating, successively, a method of producing the electronic device of  FIG. 7  by using the electronic part-containing element of the present invention.  
      Referring, first, to  FIG. 12A , the electronic part-containing element  10  of the invention is placed on an underlying layer  31  that has been formed in advance with the support member  11  on the upper side, and is fixed thereto by using a fixing material  9  which is a die-attachment film. In the case of this embodiment, the underlying film  31  is a core layer of the multi-layer wiring board.  
      Referring, next, to  FIG. 12B , the underlying layer  31  is covered with an insulating resin  32  to seal the electronic part-containing element  10 . The insulating resin used here may be a resin material that is usually used for forming an interlayer insulating film in the production of electronic devices and may be, for example, an ABF resin manufactured by Ajinomoto Co.  
      Referring, next, to  FIG. 12C , the insulating resin is removed from the upper side toward the lower side and, further, the support member  11  of the electronic part-containing element  10  is also removed. Therefore, the electrode  15  of the circuit module  12  is exposed. The electrode  15  can be exposed by various methods. Preferred methods include, for example, grinding, reactive ion etching (RIE), chemical-mechanical polishing (CMP) and wet etching.  
      After the electrode is exposed, the wiring circuit  22  can be directly formed on the electrode  15  that is formed as shown in  FIG. 12D . The wiring circuit  22  can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.  
      According to an alternative method, as shown in  FIG. 12E , a build-up resin  33  is deposited on the formed electrode  15 , a viahole is perforated at a portion of the wiring by using a laser beam to thereby form a wiring circuit  34 . The wiring circuit  34  can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.  
       FIGS. 13A  to  13 G are sectional views illustrating, successively, a method of producing the electronic device of  FIG. 8  by using the electronic part-containing element of the present invention.  
      Referring, first, to  FIG. 13A , the electronic part-containing element  10  of the invention is placed on a board  41  for temporary mounting that has been formed in advance with the support member  11  on the upper side, and is fixed thereto by using the fixing material  9  which is the die-attachment film. The board  41  used here is desirably made of a material which has rigidity and can be removed by etching or polishing. As a suitable rigid board, there can be exemplified the one made of, for example, copper or nickel. In order that the rigid board can be repetitively used, further, there may be used a composite board obtained by sticking a thin plate of copper or the like onto the glass board by using a double-sided adhesive tape.  
      Referring, next, to  FIG. 13B , the board  41  is covered with an insulating resin  32  to seal the electronic part-containing element  10 . The insulating resin used here may be a resin material that is usually used for forming an interlayer insulating film in the production of electronic devices and may be, for example, an ABF resin manufactured by Ajinomoto Co.  
      Referring, next, to  FIG. 13C , the insulating resin is removed from the upper side toward the lower side and, further, the support member  11  of the electronic part-containing element  10 , too, is removed. Therefore, the electrode  15  of the circuit module  12  is exposed. The electrode  15  can be exposed by various methods. Preferred methods include, for example, grinding, reactive ion etching (RIE), chemical-mechanical polishing (CMP) and wet etching.  
      After the electrode is exposed, a build-up resin  33  is deposited on the electrode  15  as shown in  FIG. 13D , and a viahole is perforated at a portion of the wiring by using a laser beam to thereby form a build-up wiring layer  34 . The build-up wiring layer  34  can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.  
      Thereafter, as shown in  FIG. 13E , the building-up is effected again on the resulting build-up wiring layer  34  to thereby form a build-up wiring layer  22  and an insulating layer  26 . The build-up wiring layer  22  can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.  
      Thereafter, as shown in  FIG. 13F , the whole device is turned around, and the board  41  on the upper side and the underlying fixing member  9  are successively removed. The board can be removed by various methods. When the board is made of, for example, copper, there can be used a method such as etching or polishing. When the board is made of, for example, silicon, there can be used a method such as polishing, CMP or etching. To remove the fixing member, further, there can be used a method such as polishing, RIE or peeling.  
      After removal of the board  41  and the fixing member  9 , as shown in  FIG. 13G , a pattern of the insulating layer  26  is formed as an uppermost layer to obtain the illustrated build-up wiring board.  
       FIGS. 14A  to  14 G are sectional views illustrating, successively, methods of producing the electronic devices of  FIGS. 9 and 10  by using the electronic part-containing element of the present invention.  
      Referring, first, to  FIG. 14A , the electronic part-containing element  10  of the invention is placed on the board  41  for temporary mounting that has been formed in advance with the support member  11  on the upper side, and is fixed thereto by using the fixing material  9  which is the die-attach film. The board  41  used here is desirably made of a material which has rigidity and can be removed by etching or polishing. As a suitable rigid board, there can be exemplified the one made of, for example, copper or nickel as described above.  
      Referring, next, to  FIG. 14B , the board  41  is covered with an insulating resin  32  to seal the electronic part-containing element  10 . The insulating resin used here may be a resin material that is usually used for forming an interlayer insulating film in the production of electronic devices and may be, for example, an ABF resin manufactured by Ajinomoto Co.  
      Referring, next, to  FIG. 14C , the insulating resin is removed from the upper side toward the lower side and, further, the support member  11  of the electronic part-containing element  10 , too, is removed. Therefore, the electrode  15  of the circuit module  12  is exposed. The electrode  15  can be exposed by various methods. Preferred methods include, for example, grinding, reactive ion etching (RIE), chemical-mechanical polishing (CMP) and wet etching.  
      After the electrode is exposed, a build-up resin  33  is deposited on the resulting electrode  15  as shown in  FIG. 14D .  
      Thereafter, as shown in  FIG. 14E , the whole device is turned around, and the board  41  on the upper side is successively removed. The board can be removed by various methods. When the board is made of, for example, copper, there can be used such a method as etching or polishing. When the board is made of, for example, silicon, there can be used a method such as polishing, CMP or etching.  
      Thereafter, as shown in  FIG. 14F , a through hole is perforated at a predetermined position of the insulating resin  32  and the build-up resin  33 , and is filled with copper that is plated to thereby form a conducting core  23 . Though not shown, the fixing material  9  is removed, and a build-up resin is deposited on the above portion. To remove the fixing material, further, there can be used such a method as polishing, RIE or peeling. The step of depositing the resin may be omitted, and the fixing material itself may be used as the build-up resin.  
      Finally, as shown in  FIG. 14G , a viahole is made at a predetermined portion of forming the wiring in the build-up resins  33  and  35  by using a laser beam, and build-up wiring layers  34  and  36  are formed. These build-up wiring layers can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.  
       FIGS. 15A  to  15 E are sectional views illustrating, successively, a method of producing an electronic device by using the electronic part-containing element of  FIG. 5 .  
      Referring, first, to  FIG. 15A , the electronic part-containing element  10  of the invention is placed on the underlying layer  31  that has been formed in advance with the support member  11  on the upper side, and is fixed thereto by using the fixing material  9  which is the die-attachment film. The underlying layer  31  in this embodiment is a core layer of the multi-layer wiring board. Next, the underlying layer  31  is covered with the insulating resin  32  to seal the electronic part-containing element. The insulating resin used here may be a resin material that is usually used for forming an interlayer insulating film in the production of electronic devices and may be, for example, an ABF resin manufactured by Ajinomoto Co.  
      Referring, next, to  FIG. 15B , the insulating resin is removed from the upper side toward the lower side and, further, the support member  11  of the electronic part-containing element  10 , too, is removed. Therefore, the etch-out layer  14  of the electronic part-containing element  10  is exposed. The etch-out layer  14  can be exposed by various methods. Preferred methods are, for example, grinding, reactive ion etching (RIE), chemical-mechanical polishing (CMP) and wet etching.  
      Thereafter, as shown in  FIG. 15C , the etch-out layer  14  exposed to the surface is selectively removed by etching to expose the underlying barrier layer  13 . Thereafter, as shown in  FIG. 15D , the barrier layer  13  is also removed by etching. Therefore, the electrode  15  of the circuit module  12  is exposed.  
      After the electrode is exposed as described above, a build-up wiring layer  34  is formed on the resulting electrode  15  as shown in  FIG. 15E . In this step, for example, the build-up resin is deposited, a viahole is perforated in a predetermined portion for forming wiring by using a laser beam, and the build-up wiring layer  34  is formed. The build-up wiring layer  34  can be formed by, for example, the nonelectrolytic copper plating and the electrolytic copper plating.