JP4583124B2 - Thermal head, thermal head manufacturing method, and thermal head substrate - Google Patents

Description

  The present invention relates to a thermal head incorporated in a printer mechanism.

  Conventionally, as shown in FIGS. 12 and 13, a thermal head incorporated in a printer mechanism has a rectangular substrate 101 and a heating element array 103 arranged on one end side of the substrate 101. The individual electrode wiring 104 and the common electrode wiring 105 for generating heat are connected to both ends, and a plurality of driver ICs 107 for controlling the heat generation of the respective heat generating elements 103 on the other end side of the substrate 101 are substantially the same as the heat generating element arrays 103. The driver ICs 107 are arranged in parallel and have a structure in which signal electrode wirings 106 that transmit signals from the outside are connected to the driver ICs 107.

  The connection pads for the individual electrode wiring 104 and the connection pads for the signal electrode wiring 106 connected to the driver IC 107 are integrated on the other end side of the substrate 101. For example, the connection pads for the individual electrode wiring are provided on the substrate. The connection electrodes for signal electrode wiring are arranged in one row in one or two rows along the longitudinal direction of 101.

  When manufacturing such a thermal head, as shown in FIG. 13, a plurality of thermal heads are simultaneously formed from one thermal head substrate. This manufacturing method is shown below.

  Step 1: First, the upper surface of the large substrate is divided into a plurality of partitioned regions each having a rectangular shape by the boundary line 11. One thermal head is created in each of the divided areas.

  Step 2: Next, the heating element rows 103 and electrode wirings electrically connected to the heating element rows 103 are formed in each partition region. The wiring pattern of the heating element row 103 and the electrode wiring in one partition area divided at this time is symmetrical with the wiring pattern of the heating element row 103 and the electrode wiring in another partition area adjacent to this one partitioning area. Formed to be.

  At this time, in each partition area, the heating element array 103 is formed along the long side on one end side of the partition area. A common electrode wiring 105 connected in common to each heating element is formed on the side closer to the long side of one end side of the partition area than the heating element row 103, and wraps around the end of the heating element row 103. It is drawn to the long side on the other end side of each partition area. Further, individual electrode wirings 104 that are individually connected to the respective heat generating elements extend from the respective heat generating elements toward the long side on the other end side. Furthermore, the signal electrode wiring 106 is routed from the other end side of the partition region to the vicinity of the terminal portion of the individual electrode wiring 104.

  Connection pads for connecting to the driver IC 107 are formed at the end of the individual electrode wiring and the terminal of the signal electrode wiring 106, respectively. The connection pads for the individual electrode wirings 104 and the connection pads for the signal electrode wirings 106 connected to the driver IC 107 are, for example, one or a plurality of rows of connection pads for individual electrode wirings along the longitudinal direction of the partition region. The connection pads for signal electrode wiring are arranged in a row in a staggered pattern. An array pattern corresponding to each driver IC 107 is arranged side by side by the number of driver ICs 107.

  On the large substrate, the routed individual electrode wiring 104 and common electrode wiring 105 are opposed to the individual electrode wiring 104 and the common electrode wiring 105 in other partitioned areas adjacent to the one partitioned area. Therefore, in the two partitioned regions 113 adjacent to each other on the long side, the individual electrode wirings 104 face each other and the common electrode wirings 105 face each other adjacent to each other.

  The reason why the wiring patterns of the electrode wirings are arranged point-symmetrically for each partition area 113 is that if the wiring pattern of one partition area and the wiring patterns of other adjacent partition areas are arranged in the same direction, The signal electrode wiring 106 in the other partition area and the common electrode wiring 105 in the other partition area are adjacent to each other, and the position where the common electrode wiring 105 is formed differs depending on the position shift at the time of division for each partition area. When extending from one partition area to one partition area, the common electrode wiring 105 of another partition area exists adjacent to the signal electrode wiring 106 of one partition area, and the signal electrode wiring 106 is external wiring. This is because there is a concern that the signal electrode wirings 106 may be short-circuited when connected to an external circuit wiring of a substrate (not shown) via a conductive material.

  Further, the connection pads of each partition area are also point-symmetric with respect to the connection pattern of the connection pads of one partitioned area and the connection pattern of the connection pads of another partition area adjacent to the one partition area. I am doing.

  This connection pad is used as an inspection pad for contacting the probe needle n of the inspection apparatus when inspecting the electrical connection state of the electrode wiring in each partition region 113 after this step.

  Step 3: Next, the probe needle n of the inspection device is brought into contact with the connection pad to inspect the electrical connection state of the electrode wiring in the one partition region. At this time, in order to inspect one partitioned area, a probe card having probe needles n corresponding to the arrangement pattern of the connection pads of the driver IC 107 is used so that inspection can be performed efficiently. Then, for each connection pad of each adjacent driver IC 107, the probe needle n is applied one after another and the inspection is performed. At this time, when moving between adjacent connection pads, it is not necessary to change the orientation of the probe needles n of the probe card, and it is only necessary to move the probe card in parallel.

  In the inspection performed at this time, by forming a closed circuit for measuring the resistance value of the heating element between the common electrode wiring and the individual electrode wiring, each heating element resistance value is measured, and a common electrode is connected to the common electrode wiring. The probe needle of the probe card is brought into contact with each signal electrode wiring to form a closed circuit, and it is determined whether each signal electrode wiring is short-circuited with the common electrode and the individual electrode wiring.

  Step 4: Next, the probe wiring n of the inspection device is brought into contact with the connection pad of the other partition region adjacent to the one partition region, so that the electrode wiring state in the other partition region is electrically connected. And the electrical connection state of all the partitioned regions is inspected, whereby the thermal head substrate that has finished the resistance value measurement of all the heating elements and the thermal head pass / fail judgment for each partition is obtained.

Step 5: Next, the thermal head substrate is cut for each partition region to obtain a thermal head. Thereafter, the thermal head is completed through a step of mounting the driver IC 107 in the partition region, a step of forming a protective film 109 for protecting the electrode wiring, a sealing resin 108 for sealing the driver IC 107, and the like.
Japanese Patent Laid-Open No. 10-305605

  However, in the above-described step 3 and step 4, even if the probe needle n is applied to the connection pad of another adjacent partition region after the inspection of one partition region, the one partition divided as described above is used. Since the orientation pattern of the connection pads in the region and the orientation pattern of the connection pads in the other partition regions adjacent to the one partition region are rotated by 180 degrees, the probe card is placed in the same direction. Even if the translation is continued, the arrangement pattern of the probe needles n does not correspond to the arrangement pattern of the connection pads in the other partitioned areas. For this reason, once the orientation of the probe needle n corresponds to the placement of the inspection pad, for example, the orientation of the probe card has to be rotated 180 degrees, which requires a long time for the inspection. .

  The present invention has been devised in view of the above drawbacks, and an object thereof is to provide a thermal head that can be inspected in a short time.

This onset Ming, each divided area of a large substrate consisting of a plurality of divided areas, heating element array, each electrically connected to a plurality of heat generating elements constituting the heat generating element array, and the first connection pad In a thermal head substrate comprising an electrode wiring provided, an electrode wiring provided with a second connection pad, and a test pad electrically connected to a part of the first connection pad , formed in one partition region The arrangement patterns of the first connection pad, the second connection pad, and the inspection pad thus formed are the first connection pad and the second connection formed in the other partition region. A pad formed of the first connection pad, the second connection pad, and the test pad, which is point-symmetric with each of the arrangement patterns of the test pads and the test pads, and formed in the one partition region. When the column pattern is translated, it is provided so as to overlap an array pattern of pads formed of the first connection pads, the second connection pads, and the inspection pads formed in the other partition regions. And the first connection pad connected to the inspection pad in the one partition region is a pad used for inspection of a resistance value or a short circuit, and the inspection pad in the one partition region; The first connection pads connected to the inspection pads in the other partitioned regions arranged symmetrically with respect to the connected first connection pads are pads that are not used for the inspection. The inspection pad connected to the first connection pad in the partitioned area is a pad that is not used for resistance value or short-circuit inspection, and the first connection pad in the one partitioned area; It is characterized in that the connection has been the first of the test pads connected to the connection pads of the arranged point symmetrically to the test pad the other compartments regions are pads used in the test The

Further, the present invention provides each divided area of a large substrate consisting of a plurality of divided areas, respectively are electrically connected to the plurality of heat generating elements constituting the heat generating element array, the heat generating element array, and the first connection pad In the thermal head substrate including the electrode wiring including the electrode wiring including the second connection pad and the inspection pad electrically connected to a part of the first connection pad, the thermal head substrate includes: The first connection pad, the second connection pad, and the test pad formed are arranged in a pattern in which the first connection pad, the second connection pad, A line consisting of the first connection pad, the second connection pad, and the inspection pad, which is line-symmetric with each arrangement pattern of the connection pad and the inspection pad, and is formed in the one partition region. Provided so as to overlap an array pattern of pads formed of the first connection pad, the second connection pad, and the inspection pad formed in the other partition region when the array pattern of the gate is translated. And the first connection pad connected to the inspection pad in the one partition region is a pad used for inspection of a resistance value or a short circuit, and for the inspection of the one partition region The first connection pad connected to the inspection pad in the other partition region arranged in line symmetry with the first connection pad connected to the pad is a pad that is not used for the inspection, The inspection pad connected to the first connection pad in the one partition region is a pad that is not used for resistance value or short circuit inspection, and the first connection pad in the one partition region. Wherein the de-and the first of the test pads connected to the connection pads connected the other defined areas arranged in line symmetry to the test pad was are pads used in the test It shall be the.

The thermal head manufacturing method of the present invention uses any one of the first connection pad, the second connection pad, and the inspection pad for each partition region of the thermal head substrate using the above-described thermal head substrate. to Kano pad, after testing the electrical connection state of the probe needle is brought into contact with the electrode wiring of the inspection apparatus, is separated into each of the divided area, you and forming a plurality of thermal heads.

  According to the thermal head substrate of the present invention, after inspection is performed by bringing a probe needle of an inspection device into contact with an inspection pad in one partition area, the inspection for another partition area different from the one partition area is performed. When the probe needle of the inspection apparatus is brought into contact with the pad, the other partition area can be moved without changing the direction of the probe card between adjacent partition areas without rotating the probe card. The probe needle can be made to correspond to the inspection pad, thereby shortening the time required for the inspection.

  According to the thermal head obtained from such a thermal head substrate, the time required for the above-described inspection process is shortened, so that the cost can be reduced.

  Furthermore, with such a manufacturing method, the inspection process can be simplified and the manufacturing efficiency can be increased.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a sectional view of a thermal head according to an embodiment of the present invention.

  In the thermal head of the present invention, a glaze layer 2 is formed on a long substrate 1 as shown in FIGS. 1A and 1B, and a heating element array 3 is arranged on the glaze layer 2. The individual electrode wiring 4 and the common electrode wiring 5 for generating heat are connected to both ends of each heating element. Further, a plurality of driver ICs 7 for controlling the heat generation of the respective heat generating elements are arranged on the other long side of the substrate 1 substantially in parallel with the heat generating element array 3. The signal electrode wiring 6 for transmitting the signal from is connected.

  The substrate 1 serves as a support base material for supporting the belt-like glaze layer 2, the heating element 3, the various electrode wirings 4, 5, 6 and the driver IC 7 on the upper surface thereof.

  Such a substrate 1 is formed of various materials such as an insulating material such as alumina ceramics or single crystal silicon having an oxide film deposited on its surface. For example, when made of alumina ceramics, the substrate 1 is made of alumina, silica, magnesia or the like. An appropriate organic solvent and a solvent are added to and mixed with the ceramic raw material powder to form a slurry, and a ceramic green sheet is obtained by adopting a conventionally known doctor blade method, calendar roll method, and the like. It is manufactured by punching a green sheet into a predetermined shape and firing it at a high temperature (about 1600 ° C.).

  A glaze layer 2 extending in a strip shape in the longitudinal direction is formed on one long side of the upper surface of the substrate 1.

  The glaze layer 2 has an action of storing heat generated by the heat generating element 3 and maintaining good thermal responsiveness of the thermal head.

  When such a glaze layer 2 is made of, for example, glass, a glass paste obtained by adding and mixing an appropriate organic solvent, organic binder, or the like to glass powder is applied to a predetermined upper surface of the substrate by a conventionally known screen printing method or the like. It is formed by applying to a region and processing it into a predetermined shape by employing a well-known photolithography / etching technique, and then heating it at a high temperature of 850 ° C. to 950 ° C. for a predetermined time. .

  Further, the heating element array 3 is deposited on the above-described band-shaped glaze layer 2.

  The heating element array 3 is configured by arranging and arranging each heating element in a linear or zigzag pattern at a density of 200 dpi (dot per inch), 300 dpi, or 600 dpi, each of which is TaN-based, TaSiO-based, TaSiNO-based , TiSiO-based, TiSiCO-based, and NbSiO-based resistor layers.

  The individual electrode wiring 4 is connected to one end side of each heating element, and the common electrode wiring 5 is commonly connected to the other end side, and each heating element is caused by flowing a predetermined current from the electrode wiring to the heating element. The element generates heat at a predetermined temperature.

  The individual electrode wiring 4 made of a metal material such as aluminum or copper connected to one end of each heating element described above extends from one end side of each heating element to the other end side of the upper surface of the substrate 1. Further, it is connected to an output terminal of a driver IC 7 to be described later via a connection pad provided at the end thereof, and functions as a wiring for supplying electric power from the driver IC 7 to the heating element.

  Further, the common electrode wiring 5 made of a metal material such as aluminum or copper and having one end commonly connected to each heating element is arranged on the upper surface of the substrate 1 so that the outer periphery of the region where the individual electrode wiring 4 is formed It is routed to the vicinity of the long side, is connected to the external circuit wiring of the external wiring board on the other end side, and functions as a power supply wiring for supplying power to the heating element. By this common electrode wiring 5, a voltage of about 24V is normally applied to the heating element.

  Further, on the substrate 1, the signal electrode wiring 6 is disposed so as to extend from the mounting area of the driver IC 7 to the end of the substrate 1. One end of the signal electrode wiring 6 is connected to the input terminal of the driver IC 7 through a connection pad, and the other end is connected to an external circuit wiring of an external wiring board (not shown) in the overlapping region on the end side of the substrate 1. It is connected. The signal electrode wiring 6 serves to supply a clock signal, an image data signal, a latch signal, a strobe signal, and the like from the printer to the driver IC 7.

  The connection pads of the individual electrode wiring 4 and the connection pads of the signal electrode wiring 6 connected to the driver IC 7 are, for example, a single or multiple rows of connection pads of the individual electrode wiring 4 along the longitudinal direction of the substrate 1. The connection pads for the signal electrode wiring 6 are arranged in a row in a staggered pattern. The connection pads for these electrode wirings are integrated immediately below the mounting area of the driver IC 7, and the arrangement pattern of connection pads corresponding to each driver IC 7 is arranged corresponding to the number of driver ICs 7 mounted on the thermal head. It will be.

  Further, in the individual electrode wiring 4 and the signal electrode wiring 6, there is an electrode wiring provided with a pad used only for inspection, in addition to the connection pad p2. The inspection pad p1 includes a connection pad p2 that also serves as an inspection pad and an inspection pad p1 that is used only for inspection. Then, the array pattern of the inspection pads p1 is formed in an array pattern that is substantially the same as at least one of a virtual array pattern that is point-symmetric with respect to the array pattern or a virtual array pattern that is line-symmetric with respect to the array pattern. Has been.

  The substantially same array pattern is, for example, one virtual pattern and the virtual array pattern or the other array pattern, when one array pattern is translated, without changing the pattern orientation. A pattern that overlaps and matches the array pattern or the other array pattern.

  Further, as described above, a plurality of driver ICs 7 for controlling energization to the heat generating element 3 are arranged on the upper surface of the substrate 1. The plurality of driver ICs 7 are arranged on the other end side of the substrate 1 so as to be substantially parallel to the heating element 3, and are arranged with a predetermined interval between the adjacent driver ICs 7.

  Furthermore, the driver IC 7 has an integrated circuit in which shift registers, latches, switching elements, input terminals, output terminals, etc. are integrated on one main surface of the silicon substrate at a high density. They are electrically connected via the wiring 4. The connection pad for the signal electrode wiring 6 is connected to the input terminal, and the connection pad for the individual electrode wiring 4 is connected to the output terminal via a solder bump or a gold wire for connection.

  The driver IC 7 stores the image data in the shift register through the signal electrode wiring 6 and the input terminal of the driver IC 7 while synchronizing with the clock signal, and then stores the stored image data in the latch at the timing of the latch signal. While the strobe signal is input to the switching element, the heating element 3 is energized based on the image data in the latch.

  Such driver ICs 7 are individually sealed with a sealing resin 8 made of a resin material such as a thermosetting epoxy resin.

  The sealing resin 8 is formed such that its cross-sectional shape forms a mountain shape, and functions to protect each wiring and driver IC 7 from corrosion due to moisture contained in the atmosphere.

  On the other hand, a protective film 9 is deposited on the heating element 3, the individual electrode wiring 4, and the common electrode wiring 5.

  This protective film 9 is for protecting the heating element 3, the individual electrode wiring 4 and the common electrode wiring 5 from corrosion due to contact with moisture contained in the atmosphere and wear due to sliding contact with the recording medium K. , SiC, SiN-based, SiO-based, SiON-based and other inorganic materials, glass, etc., to a thickness of 3 μm to 10 μm.

  Next, a method for manufacturing the thermal head described above will be described.

  The manufacturing method of the thermal head of this invention is produced through the 9th process from the 1st process shown in FIGS.

  Step 1: First, the upper surface of the large substrate 10 is divided into a plurality of partitioned regions each having a rectangular shape (see FIG. 2). Then, one thermal head is created in one partitioned area. This division is performed, for example, by marking the boundary line 11 on the large substrate 10. This boundary line 11 becomes a dividing groove when the large substrate 10 is divided into individual thermal heads in a later step. This scoring is performed using a laser. At this time, a positioning through-hole 12 may be provided outside the partition region on the large substrate 10 by a laser. In this way, positioning can be performed with high accuracy when the later-described glaze layer 2, heating element array 3, electrode wiring, and the like are formed in each partitioned region.

  Step 2: Next, a glaze layer 2 is formed in each partitioned area (see FIG. 3). In this step, a glass paste is applied to substantially the entire surface of the large substrate 10, and the glaze layer 2 is formed by heating and melting it. Thereafter, if necessary, the thickness of the layer may be changed by a conventionally well-known technique such as etching to form the belt-like convex glazed portion 2t.

  Step 3: Next, the heating element rows 3 and electrode wirings electrically connected to the heating element rows 3 are formed in the divided partition regions 13 (see FIG. 4). The heating element array 3 is formed on the convex glaze portion 2t described above. The wiring pattern of the heating element row 3 and the electrode wiring in one partition area divided at this time and the wiring pattern of the heating element row 3 and the electrode wiring in another partition area adjacent to this one partition area are point-symmetric. Be placed. Alternatively, the heating element row 3 and electrode wiring wiring pattern in one partition region and the heating element row 3 and electrode wiring wiring pattern in another partition region adjacent to this one partition region are Arranged in line symmetry.

  In each partition region, a heating element row 3 is formed along the long side on one end side of each partition region. The heating element row 3 is closer to the longer side than the heating element row 3 and is common to each heating element. The common electrode wiring 5 to be connected is formed and is routed to the long side on the other end side of each partition region 13 around the end of the heating element row 3. The individual electrode wiring 4 extends from each heat generating element toward the long side on the other end side.

  Further, the individual electrode wiring 4 and the common electrode wiring 5 that are routed are arranged in a point-symmetrical manner or a line-symmetrical manner in other partitioned regions adjacent to one partitioned region as described above. Accordingly, in the two partitioned regions adjacent to each other on the long side, the individual electrode wirings 4 face each other and the common electrode wirings 5 face each other and the common electrode wirings 5 face each other. The reason why the electrode wiring is arranged in this way is that if the arrangement pattern of one partition area and the arrangement pattern of another adjacent partition area are arranged in the same direction, the signal electrode wiring 6 of one partition area and the other The common electrode wiring 5 in the partition area is adjacently opposed to each other, and the position where the common electrode wiring 5 is formed extends from the other partition area into one partition area due to the positional deviation at the time of division for each section. In this case, the common electrode wiring 5 in the other partition area exists adjacent to the signal electrode wiring 6 in one partition area, and the signal electrode wiring 6 is electrically connected to the external circuit wiring of the external wiring board (not shown). This is because there is a concern that the signal electrode wiring may be short-circuited by a solder bridge or the like with the common electrode wiring when electrically connected by a material.

  Further, in this step, a plurality of rows of inspection pads p1 and connection electrode pads p2 that are electrically connected to the electrode wirings in each partition region are also formed, and adjacent to the arrangement pattern of the inspection pads p1 in one partition region. It is formed in an array pattern that is substantially the same as the array pattern of the inspection pads p1 in the partitioned area.

  Here, a procedure for determining the arrangement pattern of the inspection pads p1 based on the arrangement of the connection pads p2 of the driver IC will be described.

  The thermal head driver IC 7 is usually designed such that the output terminals are arranged in a staggered pattern of two or three rows, and the input terminals are arranged in the peripheral region of the output terminal row. If it sees the whole, it is not the structure where each terminal was uniformly arrange | positioned at equal intervals. Corresponding to the output terminal arrangement, for example, 64 or 128 pads connected to the individual electrode wiring 4 in the connection pad p2 are provided in a staggered arrangement, and connected to the signal electrode wiring 6. As described above, several pads are provided corresponding to the data signal, strobe signal, latch signal, and clock signal.

  Due to the demand for miniaturization of the thermal head, as many of the connection pads p2 of the driver IC as possible are also used as the inspection pads p1, that is, the connection pads p2 of each partition region are one partition region. It is desirable that the connection pad array pattern and the connection pad array pattern of the other partition region adjacent to the one partition region are formed to be substantially the same array pattern.

  However, since the layout of the active elements in the driver IC 7 is given priority and the design of the arrangement of the input / output terminals is restricted, all the connection pads p2 described above are arranged in consideration of the point-symmetric arrangement of the present invention. It is difficult. Therefore, in the present embodiment, the inspection pad p1 is supplementarily formed, and the inspection pads in each partition area (including the inspection pads that are also used as connection pads) are used as the inspection pads in one partition area. The arrangement pattern and the arrangement pattern of the inspection pads in the other division area adjacent to the one division area are substantially the same arrangement pattern.

  Specifically, in order to make the arrangement pattern of the inspection pads p1 the same between adjacent partition regions, first, the arrangement of the connection pads p2 for individual electrode wiring, which is larger in number than the connection electrode pads for signal electrode wiring. Is also used as the inspection pad p1, and the pad array pattern is the same as the pad array pattern when the pad array pattern is made point-symmetric. Then, a supplementary inspection pad is provided around the arrangement pattern of pads for connection / inspection of the individual electrode wirings, among the connection pads for the signal electrode wirings 6, which are in positions that cannot be used as inspection pads. Place. In this case, the entire arrangement after the inspection pads are supplementarily arranged is arranged so as to be substantially the same after being arranged point-symmetrically. Then, if necessary, the connection pad and the inspection pad are connected by an extending electrode.

  In FIG. 5, the connection pads p2 of one driver IC in one partition area are connected to the individual electrode wirings in the upper stage, and to the signal electrode wirings in the lower stage, and the upper eight pads are used as a reference. Five additional inspection electrode pads p1 are additionally formed in the lower stage.

The supplementary inspection pad p1 is electrically connected by an extended electrode wiring 14 in which an electrode wiring is extended from the corresponding connection pad p2. If a pad only for contacting the probe needle is formed, of course, the extended electrode wiring is not necessary. (See other embodiment in FIG. 11)
Step 4: Next, the electrical connection state of the electrode wiring in one partition region is inspected by bringing the probe needle 15 of the inspection device into contact with the inspection pad p1 in the one partition region (see FIG. 5). At this time, when inspecting one partition region, a probe card having probe needles 15 corresponding to the number of driver ICs 7 or a plurality of ICs is usually used for easy inspection. For example, a pad for two ICs may be used as an inspection unit, or all pads in one section may be used as an inspection unit.

  In the inspection of the electrical connection state performed at this time, the resistance value of each heating element is formed by forming a closed circuit for measuring the resistance value of the heating element between the common electrode wiring 5 and the individual electrode wiring 4 by a probe card. In addition, a closed circuit is formed in the common electrode wiring 5 and each signal electrode wiring 6, and it is determined whether each signal electrode wiring 6 is short-circuited with the common electrode 5 and the individual electrode wiring 4.

  Incidentally, in step 4 in the present embodiment, the probe needle 15 is not in contact with the additionally formed inspection pad p1. However, this is an example in which the connection pad and the inspection pad are used together. When viewed as a substantial inspection pad arrangement, the above-described point-symmetric arrangement pattern is obtained. Needless to say.

  Step 5: Next, in the inspection apparatus, the probe card having the predetermined probe needle 15 is translated, and the probe needle 15 is applied to the inspection pad p1 in the other partitioned area adjacent to the above-described one partitioned area. By making contact, the electrical connection state of the electrode wiring in the other partitioned region is inspected (see FIG. 6).

  At this time, the probe needle 15 is brought into contact with the inspection pad p1 which also serves as the connection pad p2 and the additionally added inspection pad p1 which is not used for the inspection in the previous step 4. At this time, the connection pad p2 used only for connection is not used for inspection.

  Then, by these inspection pads p1, a substantial inspection pad array pattern in one partitioned area and a substantial inspection pad array pattern in another partitioned area adjacent to the one partitioned area. Are substantially the same arrangement pattern, and in step 4, after inspecting with the probe needle 15 of the inspection device in contact with the inspection pad in one partition region, in step 5, When the test needle 15 of the inspection device is brought into contact with an inspection pad in another partition area different from the one partition area, the probe card is simply moved in parallel between the adjacent partition areas. Without rotating either the large substrate 10 or the large substrate 10, the probe needle 15 can be made to correspond to the inspection pad in the other partitioned region, thereby shortening the time required for the inspection.

  In this embodiment, the inspection closed circuit formed in the previous step 4 through the predetermined probe needle 15 and the inspection closed circuit formed in the present step 5 must be functionally different.

  That is, for example, in the previous step 4, in FIG. 5, the resistance value of the heating element connected to the individual electrode wiring must be measured by a closed circuit formed by the second probe needle from the upper left side, whereas In this process 5, in FIG. 6, the same probe needle must be inspected for the presence or absence of a short circuit of the signal electrode wiring.

  On the other hand, in the inspection apparatus, a processing algorithm for two inspection patterns of the thermal head is set in advance, and at the time of actual inspection, either of the two may be automatically determined based on the position of the probe card. . That is, for the case of inspecting with a closed circuit corresponding to the array pattern of one partitioned area and the case of inspecting with a closed circuit corresponding to the array pattern of another adjacent partitioned area, for each thermal head substrate to be inspected Create a probe needle pair inspection pattern correspondence table in advance and refer to that table. In the case of resistance measurement, it is determined whether the resistance value is within the specified resistance value range, and at the same time, the resistance value is saved. Is determined based on whether or not a current flows in the closed circuit. Of course, hardware for measurement and software if necessary are incorporated in the inspection apparatus.

  Thus, as described above, by inspecting the electrical connection state of all the partitioned regions, it is possible to obtain a thermal head substrate that has finished the resistance value measurement of all the heating elements and the thermal head pass / fail determination for each partition. it can.

  Step 6: Next, the thermal head substrate is divided (see FIG. 7).

  At this time, the thermal head substrate is divided for each partitioned region along the boundary line 11 formed by the laser in step 1.

  Step 7: Next, among the divided partitioned areas, those determined to be non-defective in Step 5 are the heating element 3, the individual electrode wiring 4 and the common electrode wiring 5 formed on each partitioned area. A protective film 9 is deposited on the upper surface (see FIG. 8).

  This protective film 9 is made of SiC, SiN-based, SiO-based, SiON-based or other inorganic materials, glass, etc., and is formed by a thin film formation technique (sputtering method, vapor deposition method, CVD method, etc.) And a thickness of 3 μm to 10 μm.

  Step 8: Next, a plurality of driver ICs 7 for controlling energization to the heat generating elements 3 are mounted on the connection pads in the divided partition areas via a conductive material (see FIG. 9). The plurality of driver ICs 7 are arranged on the other end side of the substrate 1 so as to be substantially parallel to the heating element array 3 and are arranged with a predetermined interval between adjacent driver ICs 7.

  Step 9: Finally, each driver IC 7 is individually sealed with a sealing resin 8 made of a resin material such as a thermosetting epoxy resin (see FIG. 10). The sealing resin 8 is formed by, for example, applying a predetermined liquid precursor made of an epoxy resin so as to cover the driver IC 7 on the substrate 1 and heating and polymerizing the same at 130 ° C. to 150 ° C., Thereby, the thermal head is completed.

  Thus, the thermal head manufactured by the manufacturing method of the present invention has a driver between the individual electrode wiring 4 and the common electrode wiring 5 while the recording medium is brought into sliding contact with the heating element array 3 formed on the upper surface of the substrate 1 by the platen roller. A power supply is applied as the IC 7 is driven to cause each heating element to individually generate Joule heat in response to a printing signal and to conduct the generated heat to the recording medium to form a print on the recording medium. Function as a thermal head.

  In addition, this invention is not limited to the form mentioned above, A various change and improvement are possible in the range which does not deviate from the summary of this invention.

  For example, various patterns can be considered for the arrangement of the inspection pads. As an example, as shown in FIG. 11, the connection pads p3 connected to the individual electrode wiring 4 are arranged in two rows in a staggered manner, and the connection connected to the signal electrode wiring at the lower stage of the connection pad group The case where the pad for p4 is arranged is shown. In this case, with reference to the connection pad group connected to the individual electrode wirings 4 arranged in a staggered manner as described above, in consideration of the point symmetry referred to in the present invention, the two connection pads p3 are arranged between the columns. In addition, by arranging the supplementary inspection pad p5 of the connection pad p4, so-called inspection pads (including inspection pads that also serve as connection pads) in each partition region can be used as the inspection pads in one partition region. The arrangement pattern and the arrangement pattern of the inspection pads in the other division area adjacent to the one division area are arranged so as to be substantially the same arrangement pattern. The connection pads are connected by the extending electrode e. In this case, even in a thermal head having a heat generating element having a relatively high density of 400 dpi (dot per inch) or 600 dpi, staggered arrangement of connection pads, extension electrode wirings 14 and complementary inspection pad formation, High-density wiring and high-density pad arrangement are possible, and the thermal head can be miniaturized, and at the same time, the resistance value measurement, short-circuit inspection, and the like can be performed at high speed and accurately. .

(A) is sectional drawing of the thermal head which concerns on one Embodiment of this invention, (B) is the top view. It is a top view which shows the 1st process of the manufacturing method of this invention. It is sectional drawing which shows the 2nd process of the manufacturing method of this invention. It is a top view which shows the 3rd process of the manufacturing method of this invention. (A) is a top view which shows the 4th process of the manufacturing method of this invention, (B) is the partial expansion schematic diagram. (A) is a top view which shows the 5th process of the manufacturing method of this invention, (B) is the partial expansion schematic diagram. It is sectional drawing which shows the 6th process of the manufacturing method of this invention. It is sectional drawing which shows the 7th process of the manufacturing method of this invention. It is a top view which shows the 8th process of the manufacturing method of this invention. It is sectional drawing which shows the 9th process of the manufacturing method of this invention. It is a top view of the thermal head board | substrate concerning other embodiment of this invention. It is sectional drawing of the conventional thermal head. (A) is a top view which shows the test | inspection process of the conventional manufacturing method, (B) is the partial expansion schematic diagram.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 2 ... Glaze layer 2t ... Convex part glaze part 3 ... Heat generating element row | line | column ... Individual electrode wiring 5 ... Common electrode wiring 6 ... Signal electrode wiring 7 ...・ Driver IC
8 ... Sealing resin 9 ... Protective film 10 ... Large substrate 11 ... Boundary line (divided groove)
DESCRIPTION OF SYMBOLS 12 ... Through-hole 13 ... Partition area | region 14 ... Extension electrode wiring 15 ... Probe needle p1 ... Inspection pad p2 ... Connection pad of inspection apparatus

Claims (3)

A heating element array, an electrode wiring electrically connected to each of the plurality of heating elements constituting the heating element array, and having a first connection pad ; In a thermal head substrate including an electrode wiring having a second connection pad and a test pad electrically connected to a part of the first connection pad , the first formed in one of the partition regions. The arrangement patterns of the connection pads, the second connection pads, and the inspection pads are the first connection pads, the second connection pads, and the inspection patterns formed in the other partitioned areas. An arrangement pattern of pads that is point-symmetric with each arrangement pattern of pads for use and includes the first connection pads, the second connection pads, and the inspection pads formed in the one partition region Are arranged so as to overlap an array pattern of pads composed of the first connection pads, the second connection pads, and the inspection pads formed in the other partition region when The first connection pad connected to the inspection pad in the one partition region is a pad used for resistance value or short-circuit inspection, and is connected to the inspection pad in the one partition region. Further, the first connection pad connected to the inspection pad in the other partition region arranged symmetrically with respect to the first connection pad is a pad not used for the inspection, and the one partition The inspection pad connected to the first connection pad in the region is a pad not used for resistance value or short-circuit inspection, and is connected to the first connection pad in the one partition region The thermal head substrate whose serial first of said test pads connected to the connection pads of the inspection the other defined areas which are arranged point symmetrically to the pad may be a pad used in the test . A heating element array, an electrode wiring electrically connected to each of the plurality of heating elements constituting the heating element array, and having a first connection pad ; In a thermal head substrate including an electrode wiring having a second connection pad and a test pad electrically connected to a part of the first connection pad , the first formed in one of the partition regions. The arrangement patterns of the connection pads, the second connection pads, and the inspection pads are the first connection pads, the second connection pads, and the inspection patterns formed in the other partitioned areas. A pad arrangement pattern that is symmetrical with each arrangement pattern of the pads and includes the first connection pads, the second connection pads, and the inspection pads formed in the one partition region. Are arranged so as to overlap an array pattern of pads composed of the first connection pads, the second connection pads, and the inspection pads formed in the other partition region when The first connection pad connected to the inspection pad in the one partition region is a pad used for inspection of resistance value or short circuit.
The first connection pad connected to the inspection pad of another partition area arranged symmetrically to the first connection pad connected to the inspection pad of the one partition area Is a pad that is not used for the inspection, and the inspection pad that is connected to the first connection pad of the one partition region is a pad that is not used for a resistance value or short circuit inspection, and the one partition region The inspection pad connected to the first connection pad in the other partition region arranged in line symmetry with the inspection pad connected to the first connection pad is used for the inspection. A thermal head substrate characterized by being a pad . 3. A probe needle of an inspection apparatus on any one of the first connection pad, the second connection pad, and the inspection pad for each partition region of the thermal head substrate according to claim 1 or 2. And a plurality of thermal heads are formed by separating each partition region after inspecting the electrical connection state of the electrode wiring.

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