JP4378889B2 - IC chip mounting method in high frequency module - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an IC chip mounting method in a high frequency module.
[0002]
[Prior art]
Conventionally, an element that handles high-frequency signals such as microwaves and millimeter waves is made into one chip and the chip is modularized. At this time, there is a demand for improving the yield.
[0003]
[Problems to be solved by the invention]
The present invention has been made under such a background, and an object of the present invention is to provide an IC chip mounting method in a high-frequency module capable of effectively using module components.
[0004]
[Means for Solving the Problems]
The method of mounting an IC chip in a high-frequency module according to claim 1 is characterized in that an MMIC that replaces the MMIC is placed on an MMIC that has a defective portion or a faulty MMIC. It is said. Conventionally, when an MMIC is defective or fails, it can not be reproduced because the entire module is defective. However, according to the present invention, the MMIC that replaces the MMIC is stacked on the MMIC. By arranging in this way, the module component can be effectively used. Furthermore, since it is not necessary to install a ground electrode on the back surface using a coplanar waveguide on the MMIC line as an alternative to the above, a non-conductive adhesive having good adhesive strength and workability can be used.
[0006]
According to the mounting method of the IC chip in the high-frequency module according to any one of claims 2 to 5 , the ground electrode of the microstrip line or the grounded coplanar waveguide has a stable potential. In particular, as in claim 6, after removing the bonding wire connecting the line to the defective or faulty MMIC, the MMIC that has been defective is superposed on the replacement MMIC. If it is arranged and the MMIC instead of this and the line are connected by a bonding wire, it becomes practically preferable.
[0007]
When applied to the mounting of millimeter wave band MMICs of 30 GHz or more, as described in claim 7 , it is preferable as mounting of a module having a higher component cost than the manufacturing cost.
[0008]
According to the mounting method of the IC chip in the high-frequency module according to claim 8 , when the MMIC is arranged in a stacked manner, the length of the bonding wire is designed to be the shortest when the MMIC is stacked in a plurality of stages. It is possible to compensate for the deterioration of the loss caused by stacking a plurality of MMICs.
[0009]
According to the method for mounting an IC chip in a high-frequency module according to claim 10 , if the length of the bonding wire is minimized when the MMICs are stacked in two stages, the module failure is statistically detected once per MMIC. Often within. Therefore, it is possible to improve the module yield by making it possible to reproduce the best characteristics when a defect occurs only once.
[0010]
According to the mounting method of the IC chip in the high-frequency module according to claim 11 , a plurality of MMICs having two or more stages of MMICs are provided rather than variations in the length of the bonding wire in a normal state (when MMICs are mounted in one stage). If it is designed to improve the characteristics of the bonding wire when it is mounted, the loss of the bonding wire will be lost when the MMICs are stacked in multiple stages. By designing it to be minimized, it is possible to compensate for loss degradation caused by stacking a plurality of MMICs.
[0011]
According to the method of mounting an IC chip in a high-frequency module according to claim 12 , if the loss of the bonding wire is minimized when the MMICs are stacked in two stages, the module failure is statistically detected once per MMIC. Often within. Therefore, it is possible to improve the module yield by making it possible to reproduce the best characteristics when a defect occurs only once. In particular, as in the thirteenth aspect , when performed on a millimeter wave band MMIC of 30 GHz band or higher, it is preferable for mounting a module having a higher component cost than the manufacturing cost.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a high frequency module according to the present embodiment. This module handles millimeter waves in the high frequency range.
[0014]
In FIG. 1, an MMIC 20 and a line substrate 30 are mounted on a base (carrier) 10. An active element, a matching circuit, and the like are formed in the MMIC 20, and a millimeter wave signal flowing through the MMIC 20 is processed. For example, amplification by an active element is performed. Regarding the line substrate 30, tetrafluoroethylene resin (fluorine resin) is used as the material of the substrate. The line substrate 30 is formed with lines such as a microstrip line, a coplanar waveguide, and a grounded coplanar waveguide. Further, a chip component 31 is mounted on the upper surface of the line substrate 30.
[0015]
A lid member 50 is disposed on the base 10, and the lid member 50 hermetically seals the MMIC 20 and the line substrate 30. An external connection connector 40 is mounted on the base 10. The lines of the line substrate 30 and the connection terminals 41 of the external connection connector 40 are connected by bonding wires 82.
[0016]
Here, regarding the MMIC 20, the MMIC 20 is mounted on the base 10, but the MMIC 70 that replaces the MMIC 20 is disposed on the MMIC 20 having a defective portion.
[0017]
FIG. 2 shows an enlarged view of the MMIC arrangement portion.
In FIG. 2, a square hole 30a is formed in the central portion of the line substrate 30, and the MMIC 20 having a defective portion is mounted in the hole 30a. An alternative MMIC 70 is fixed on the MMIC 20 by an adhesive 60. Further, the substrate thickness t2 of the line substrate 30 is thicker than the substrate thickness t1 in each MMIC 20, 70 (t2> t1). On the other hand, matching circuits 32 and 33 are formed at the ends of the line on the upper surface of the line substrate 30. The pads 71 and 72 of the MMIC 70 and the matching circuits 32 and 33 of the line substrate 30 are electrically connected by bonding wires 80 and 81.
[0018]
Next, the manufacturing process of the high frequency module will be described.
FIG. 3 is a diagram illustrating a work order in manufacturing.
First, as shown in FIG. 4, a base 10 is prepared. And the conductive paste which is an adhesive agent before hardening is printed on the predetermined area | region in the upper surface of the base 10 (code | symbol 100 in FIG. 3), and as shown in FIG. It arrange | positions, heats and hardens | cure | bonds together (code | symbol 101 in FIG. 3). Furthermore, a conductive paste as an adhesive before curing is applied to a predetermined region on the upper surface of the base 10 and a predetermined region on the upper surface of the line substrate 30 (reference numeral 102 in FIG. 3), as shown in FIG. The MMIC 20, the chip component 31, and the connector 40 are placed thereon and fixed by heating and curing (reference numeral 103 in FIG. 3). Subsequently, as shown in FIG. 7, bonding between the MMIC 20 and the line of the line substrate 30 and between the line of the line substrate 30 and the connection terminal 41 of the connector 40 is performed by wires 82, 83, and 84 (in FIG. 3). 104).
[0019]
In this state, as indicated by reference numeral 105 in FIG. 3, the DC bias current is measured using the probe pin, and it is inspected whether or not the value is within a predetermined range. When a defect occurs in this inspection, the following is performed.
[0020]
First, at 106 in FIG. 3, the bonding wires 83 and 84 between the MMIC 20 and the line of the line substrate 30 are removed as shown in FIG. Then, as shown in FIG. 9, after applying the adhesive 60 on the MMIC 20, the MMIC 70 that replaces the MMIC 20 is mounted. Further, as shown in FIG. 10, the MMIC 70 and the line of the line substrate 30 are bonded with wires 80 and 81 (reference numeral 107 in FIG. 3).
[0021]
In this state, as indicated by reference numeral 105 in FIG. 3 again, the DC bias current is measured using the probe pin to check whether or not the value is within a predetermined range. If no defect occurs in this inspection, the following is performed.
[0022]
First, as shown in FIG. 11, a lid member 50 is disposed on a base 10, and a resin 51 is disposed at a contact portion of the lid member 50 with the base 10, and heated and cured to be sealed (in FIG. 3). 108). Further, the hole 52 of the lid member 50 is brazed and sealed under a nitrogen atmosphere (reference numeral 109 in FIG. 3). Thereby, the inside of the lid member 50 becomes a nitrogen atmosphere. As a result, the module of FIG. 1 is obtained.
[0023]
As described above, as a method for mounting an IC chip in a high-frequency module, the MMIC 70 that replaces the MMIC 20 is arranged on the MMIC 20 having a defective portion in a stacked state. Therefore, conventionally, if the MMIC is a defective product, it cannot be reproduced because the entire module is defective. However, according to the present embodiment, the MMIC 70 that replaces the MMIC 20 is arranged in a stacked state. Thus, it is possible to improve the yield by effectively using the component parts of the module. Further, the module can be regenerated and waste can be reduced.
[0024]
In particular, the MMIC 20 and the line substrate 30 are mounted on the base 10 as shown in FIGS. 6 and 7, the signal lines of the MMIC 20 and the line substrate 30 are electrically connected, and the module is inspected. The electrical connection members (bonding wires 83 and 84) to the line substrate 30 in the MMIC 20 in the module that has been removed are removed, and the MMIC 70 that replaces the MMIC 20 is overlaid on the MMIC 20 as shown in FIGS. In addition, the MMIC 70 to be replaced and the signal line of the line substrate 30 were electrically connected by bonding wires 80 and 81. In this way, after removing the bonding wires 83 and 84 that connect the line to the MMIC 20 with the defective portion, the MMIC 70 that replaces the MMIC 20 is arranged on the MMIC 20 with the defective portion, Since the MMIC 70 and the line are connected by the bonding wires 80 and 81, it is practically preferable.
[0025]
Further, since the MMICs 20 and 70 handle the millimeter wave band of 30 GHz or higher (applying to the mounting of the millimeter wave band MMIC of 30 GHz or higher), the MMICs 20 and 70 are preferable for mounting modules having higher component costs than manufacturing costs. Become.
[0026]
Next, a method for mounting the MMIC 70 that replaces the defective MMIC 20 and electrically connecting it to the line will be described.
As shown in FIG. 12, a coplanar waveguide is used for the line of the MMIC 70 that replaces the MMIC 20 having the defective portion, and the MMIC 20 is replaced on the MMIC 20 having the defective portion via the non-conductive adhesive 61. The MMIC 70 is bonded in a stacked state. As described above, in the case of the coplanar waveguide, since the ground electrode on the back surface is not necessary, it is possible to use the nonconductive adhesive 61 having good adhesive strength and workability.
[0027]
Further, as shown in FIG. 13, a coplanar waveguide with a ground (or a microstrip line) is used for the line of the MMIC 70 instead of the MMIC 20 having the defective portion, and the through-hole portion 21 of the wiring in the MMIC 20 having the defective portion A conductive paste (adhesive before curing) 62 is applied to the entire upper surface (or part) of the upper surface of the MMIC 20 so as to be conductive, and the MMIC 70 to be replaced is adhered to the conductive paste 62 in a state of being overlaid. . As a result, the ground electrode 73 of the grounded coplanar waveguide (or microstrip line) has a stable potential.
[0028]
Further, as shown in FIG. 14, a grounded coplanar waveguide (or microstrip line) is used for the line of the MMIC 70 that replaces the MMIC 20 having a defective portion, and the ground electrode 73 on the back surface of the MMIC 70 that performs the replacement is electrically conductive. A paste (adhesive before curing) 63 is applied, and the MMIC 70 to which the conductive paste 63 is applied is adhered on the MMIC 20 with the defective portion in a state of being electrically connected to the through-hole portion 22 of the wiring of the MMIC 20 with the defective portion. . As a result, the ground electrode 73 of the grounded coplanar waveguide (or microstrip line) has a stable potential.
[0029]
Further, as shown in FIG. 15, a microstrip line (or a coplanar waveguide with a ground) is used for the line of the MMIC 70 that replaces the MMIC 20 having a defective portion, and a conductive paste (before curing) is formed on the MMIC 20 having the defective portion. Adhesive) 64 is applied, and the ground electrode 74 of the MMIC 70 to be replaced is placed on the MMIC 20 with the defective portion by using the conductive paste 64 on the MMIC 20 with the defective portion, using the side surface of the MMIC 20 with the defective portion. It adheres in a state where it is electrically connected to the ground electrode 23 or the base 10. As a result, the ground electrode 74 of the microstrip line (or the coplanar waveguide with ground) has a stable potential.
[0030]
Further, as shown in FIG. 16, a microstrip line (or a coplanar waveguide with a ground) is used for the line of the MMIC 70 that replaces the MMIC 20 with the defective portion, the MMIC 20 with the defective portion is crushed, and the MMIC 20 of the MMIC 20 is formed on the upper surface thereof. A conductive paste (adhesive before curing) 65 is applied so as to soak into the crack 24, and a substitute MMIC 70 is placed on the MMIC 20 with the ground electrode 25 or the base 10 on the back surface of the MMIC 20 having a defective portion. Adhere in a conductive state. As a result, the ground electrode 75 of the microstrip line (or the coplanar waveguide with ground) has a stable potential.
[0031]
In addition, as shown in FIG. 17, a recess 11 is formed on the upper surface of the base 10, and the bottom surface of the recess 11 is used as an arrangement region of the MMIC 20, and the MMIC 20 is higher than the height H1 on the upper surface of the MMIC 20 where there is a defective portion. The height H2 of the line side part to be connected to is increased. Therefore, when the MMICs are stacked, the MMIC can be designed so that the length of the bonding wire becomes the shortest when a plurality of stages are stacked, and the loss deterioration due to the stacking of the MMICs is compensated. be able to.
[0032]
In addition, as shown in FIG. 18, by forming the recess 11, the length of the bonding wire is made the shortest in a state where the MMICs 20 and 70 are stacked in two stages. Alternatively, as shown in FIG. 19, by optimizing the thickness of the line substrate 30, the length of the bonding wire is made the shortest in a state where the MMICs 20 and 70 are stacked in two stages. If the length of the bonding wire is made the shortest when two MMICs are stacked, statistically, the module failure is statistically within one time per MMIC. Therefore, it is possible to improve the module yield by making it possible to reproduce the best characteristics when a defect occurs only once.
[0033]
Further, as shown in FIG. 2, impedance mismatch due to the connection of bonding wires 80 and 81 to at least one of the signal input portion of the MMIC 70 and the connection portion of the line and the signal output portion of the MMIC 70 and the connection portion of the line. The matching circuits 32 and 33 for compensating the above are provided, and a wide band design is performed with respect to the length of the bonding wire when the matching MMIC 70 is superimposed on the matching circuits 32 and 33. More characteristic for bonding wire length variation when multiple MMICs or more than two stages are mounted rather than normal bonding wire length variation Is designed so that the loss of the bonding wire is minimized when the MMICs are stacked in a plurality of stages when the MMICs are stacked, so that the MMICs are stacked in a plurality of stages. Loss deterioration can be compensated.
[0034]
In particular, a wide band design is performed so that the bonding wire loss is minimized (see FIG. 20) when the replacement MMIC 70 is superimposed on the matching circuits 32 and 33 by one stage (see FIG. 20). Wideband design). Specifically, for example, the line length L and the line widths W1 and W2 in FIG. 2 are adjusted.
[0035]
In this way, if the loss of the bonding wire is minimized when the MMICs are stacked in two stages, as described above, the module failure is often statistically within one time per MMIC, When the defect occurs only once, it is possible to improve the module yield by making it possible to reproduce the best characteristics. In particular, when the wideband design is performed for a millimeter wave band MMIC of 30 GHz band or higher, it is preferable as a module mounting having a higher component cost than the manufacturing cost.
[0036]
In the above description, the MMIC 70 that replaces the MMIC 20 with the defective portion is described as being superposed on the MMIC 20 with the defective portion. However, the MMIC instead of the MMIC 20 with the defective portion is not overlapped with the MMIC 20 with the defective portion. May be. That is, a high-frequency module that has been shipped once may be collected, and a replacement MMIC may be placed on the failed MMIC for inspection and then shipped. Even in this case, the module components can be effectively used.
[0037]
Further, the base 10 and the line substrate 30 may be integrated to form a line on the base 10 and be connected to the MMIC.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a high-frequency module according to an embodiment.
FIG. 2 is a diagram for explaining details of a line substrate and an MMIC.
FIG. 3 is a mounting process diagram.
FIG. 4 is a view for explaining a mounting process.
FIG. 5 is a view for explaining a mounting process.
FIG. 6 is a view for explaining a mounting process.
FIG. 7 is a view for explaining a mounting process.
FIG. 8 is a view for explaining a mounting process.
FIG. 9 is a view for explaining a mounting process.
FIG. 10 is a view for explaining a mounting process.
FIG. 11 is a view for explaining a mounting process;
FIG. 12 is a diagram for explaining the implementation of the MMIC.
FIG. 13 is a diagram for explaining the implementation of the MMIC.
FIG. 14 is a diagram for explaining the implementation of the MMIC.
FIG. 15 is a diagram for explaining the implementation of the MMIC.
FIG. 16 is a diagram for explaining the implementation of the MMIC.
FIG. 17 is a diagram for explaining the implementation of the MMIC.
FIG. 18 is a diagram for explaining the implementation of the MMIC.
FIG. 19 is a diagram for explaining the implementation of the MMIC.
FIG. 20 is a diagram for explaining the design of a matching circuit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Base, 11 ... Recessed part, 20 ... MMIC, 21 ... Through-hole part, 22 ... Through-hole part, 23 ... Ground electrode, 24 ... Crack, 25 ... Ground electrode, 30 ... Line substrate, 32 ... Matching circuit, 33 ... Matching circuit, 40 ... Connector, 50 ... Lid, 61 ... Non-conductive adhesive, 62 ... Conductive paste, 63 ... Conductive paste, 64 ... Conductive paste, 70 ... MMIC, 80, 81, 82, 83 84 Bonding wire.

Claims (13)

The MMIC (20) having a defective portion mounted on the base (10) or the MMIC (70) that replaces the failed MMIC is arranged in a state of being superimposed on the MMIC (20) and the line. A method of mounting an IC chip in a high-frequency module that is electrically connected ,
Line using coplanar waveguide to the MMIC (70) to the cash spite of a defective portion MMIC (20) or failed MMIC, a defective portion MMIC (20) or on the failed MMIC, nonconductive adhesive A method of mounting an IC chip in a high-frequency module, characterized in that an MMIC (70) that replaces the MMIC (20) is bonded via an agent (61) in a stacked state . The MMIC (20) having a defective portion mounted on the base (10) or the MMIC (70) that replaces the failed MMIC is arranged in a state of being superimposed on the MMIC (20) and the line. met IC chip mounting method in the high frequency modules to be electrically connected,
Using a grounded coplanar waveguide or microstrip line for the MMIC (20) with a defective part or the MMIC (70) to replace the failed MMIC , wiring with the defective MMIC (20) or the defective MMIC A conductive paste (62) is applied to a part or the whole of the upper surface of the MMIC (20) so as to be electrically connected to the through-hole portion (21) of the MMIC , and the MMIC is substituted on the conductive paste (62). (70) A method of mounting an IC chip in a high-frequency module, characterized in that bonding is performed in a stacked state. The MMIC (20) having a defective portion mounted on the base (10) or the MMIC (70) that replaces the failed MMIC is arranged in a state of being superimposed on the MMIC (20) and the line. met IC chip mounting method in the high frequency modules to be electrically connected,
Line with the grounded coplanar waveguide or microstrip lines to the MMIC (70) take the place of a defective portion MMIC (20) or failed MMIC, the back surface of the ground electrode of the MMIC (70) to the place (73 The conductive paste (63) is applied to the MMIC (20) having a defective portion or the MMIC (70) having the conductive paste (63) applied on the failed MMIC. 20) or a method of mounting an IC chip in a high-frequency module, wherein the IC chip is bonded in a conductive state to a through-hole portion (22) of a failed MMIC wiring . The MMIC (20) having a defective portion mounted on the base (10) or the MMIC (70) that replaces the failed MMIC is arranged in a state of being superimposed on the MMIC (20) and the line. met IC chip mounting method in the high frequency modules to be electrically connected,
A grounded coplanar waveguide or microstrip line is used for the MMIC (20) with a defective part or the MMIC (70) to replace the failed MMIC, and the MMIC (20) with a defective part or the defective MMIC is placed on the line. A conductive paste (64) is applied, and the ground electrode (74) of the MMIC (70) to be replaced is placed on the MMIC (20) via the conductive paste (64). ) Or a faulty MMIC side surface is used to adhere to the ground electrode (23) or the base (10) on the back of the faulty MMIC (20) or the faulty MMIC. IC chip mounting method in a high-frequency module. The MMIC (20) having a defective portion mounted on the base (10) or the MMIC (70) that replaces the failed MMIC is arranged in a state of being superimposed on the MMIC (20) and the line. met IC chip mounting method in the high frequency modules to be electrically connected,
Using a grounded coplanar waveguide or microstrip line on the MMIC (20) with a defective part or the MMIC (70) to replace the failed MMIC, crush the MMIC (20) with a defective part or the defective MMIC, the MMIC (20) conductive Bae one strike (65) so as to go bleeding crevices (24) was applied to the upper surface, on of the MMIC (20), MMIC to the place (70) the defective portions A method of mounting an IC chip in a high-frequency module, wherein the IC chip is bonded in a conductive state to a ground electrode (25) or a base (10) on the back surface of a certain MMIC (20) or a failed MMIC. In the mounting method of the IC chip in the high frequency module according to any one of claims 1 to 5 ,
After removal of the MMIC (20) or a bonding wire connecting the failed MMIC and the line (83, 84) with a defective portion, on the a defective portion MMIC (20) or failed MMIC, the MMIC ( 20) An MMIC (70) that replaces 20) is placed in an overlapping state, and the MMIC (70) and the line are connected by bonding wires (80, 81) . Implementation method. In the mounting method of the IC chip in the high frequency module according to any one of claims 1 to 6 ,
A method of mounting an IC chip in a high-frequency module, wherein the MMIC (20, 70) handles a millimeter wave band of 30 GHz or more . In the mounting method of the IC chip in the high frequency module according to any one of claims 1 to 7 ,
A high frequency characterized in that the height (H2) of the line side portion connected to the MMIC (20) is higher than the height (H1) on the upper surface of the MMIC (20 ) having a defective portion or the failed MMIC. IC chip mounting method in module. In the mounting method of the IC chip in the high frequency module according to claim 8 ,
A concave portion (11) is formed on the upper surface of the base (10), and the bottom surface of the concave portion (11) is used as an arrangement region of the MMIC (20), whereby the upper surface of the defective MMIC (20) or the failed MMIC. A method of mounting an IC chip in a high-frequency module, characterized in that the height (H2) of the line side portion connected to the MMIC (20) is made higher than the height (H1) in FIG. In the mounting method of the IC chip in the high frequency module according to claim 8 or 9,
The MMIC (20, 70) in two-tiered state, IC chip mounting method in the high-frequency module, characterized in that the length of the bonding wire was so that a shortest. In the mounting method of the IC chip in the high frequency module according to any one of claims 1 to 10,
Impedance mismatch due to the bonding wire (80, 81) is connected to at least one of the signal input portion of the MMIC (70) and the connection portion of the line and the signal output portion of the MMIC (70) and the connection portion of the line. The matching circuit (32, 33) to be compensated is provided, and a wide band design is performed for the length of the bonding wire when the matching MMIC (70) is superimposed on the matching circuit (32, 33). IC chip mounting method in a high-frequency module. In the mounting method of the IC chip in the high frequency module according to claim 11 ,
A matching circuit (32, 33), IC in the high-frequency module, characterized in that the loss of the bonding wire when the overlapped only one step MMIC (70) take the place has a wideband designed to minimize the row Migihitsuji chip How to implement In the mounting method of the IC chip in the high frequency module according to claim 12 ,
A method for mounting an IC chip in a high-frequency module, characterized in that the broadband design is performed for a millimeter wave band MMIC of 30 GHz band or higher .

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