JPH06834Y2 - Lead frame for semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a lead frame for a semiconductor device, that is, a lead frame used for a device having a semiconductor chip.

[Outline of device]

A lead frame for a semiconductor device according to the present invention is a guide for mounting a semiconductor chip on a peripheral portion of a die pad part on which a semiconductor chip is mounted with two or more desired different angles with respect to a reference line of the die pad part. By having a plurality of parts, the semiconductor chip can be mounted in a desired direction indicated by the guide part, and can be generally used for semiconductor chips of different shapes, and the mounting direction is specified for each guide part. It is designed to be accurately defined in one direction.

[Background of the Invention] A semiconductor device includes a semiconductor chip that constitutes the device.
Some of them need to be mounted with a certain directionality. For example, in a semiconductor device used as a photodetector for a compact disc CD, it is necessary to mount a semiconductor chip at a position having a certain directionality in order to obtain information on the disc. This is because the direction in which the pickup moves on the disk is determined by the position of the motor that is the drive source, and therefore the most efficient position for receiving the signal is determined.

However, the direction is not the same for all CDs, and will change depending on the CD model. As described above, the moving direction of the pickup is determined by the position of the motor. However, since the installation position of the motor differs depending on the model, the moving direction of the pickup also differs depending on the model. Along with this, the installation direction of the photodetector is changing.

That is, the mounting direction of the photodetector must be fixed for a specific model, but it must be fixed for other models.

On the other hand, conventionally, various lead frames for semiconductor devices have been proposed. However, using the lead frame,
The above-mentioned technology that attempts to define the mounting direction for each model has not been proposed yet.

For example, Japanese Patent Laid-Open No. 58-18948 discloses a technique relating to a lead frame capable of accurately setting the mounting position of a semiconductor element, which shows a structure for positioning a semiconductor chip at the center of a bed (die pad). "2
To accurately set the original normal mounting position of the semiconductor device by using two beds that are orthogonal to each other and leave at least the short side of the rectangle, and have a plate-like shape with at least eight sides. It is described that it is possible to distinguish a semiconductor element mounted at an abnormal position from a non-defective product. However, this conventional technology does not consider that the mounting direction is different for each model, and in the end, there is no idea that the mounting direction of the semiconductor chip is specified for each model, and naturally such an effect is expected. It cannot be done.

Further, Japanese Utility Model Laid-Open No. 56-84360 discloses in its specification (Japanese Patent Application No. 54-167257) that at least three through holes are formed in a semiconductor element setting region to easily position a semiconductor element, and wire We will disclose a lead piece with a structure that allows proper bonding, but this is a positioning guide in order to prevent the semiconductor element from shifting or rotating within the short semiconductor element setting area. This is a technology that only three or more through holes corresponding to the corners of the semiconductor element are provided in order to accurately position the semiconductor element within the smallest semiconductor element setting area. No consideration has been given to making the directions different, and in the end, there is no concept of defining the mounting direction of the semiconductor chip for each model, and naturally such an effect can be expected. It is the casting.

It is necessary to specify the mounting direction of the semiconductor chip for each model described above, for example, the photodetector mounting direction must be fixed for certain models of CD photodetectors, but different fixed mounting for other models. The necessity of taking a direction will be described in more detail with reference to FIG. 8 for explaining an embodiment of the present invention, which will be described later in detail. This FIG. 8 (a)
(C) is a layout view when the semiconductor chip 2'constituting the photodetector for CD is mounted. In FIG. 1 (a), the semiconductor chip 2'is shown by the vertical line l ( Angle (with respect to the reference line) is 0
The degree is 30 degrees in the case of FIG. 8 (b), and FIG. 8 (c)
In the case of, it is necessary to set it to 45 degrees. Such a direction is C
Since it is determined according to the locus of the pickup of D, it needs to be constant in the same model, and this angle changes as described above in different models. (1 'in each figure in FIG. 8 is a lead frame,
K indicates a cathode).

[Problems to be solved by the invention]

When the installation direction of the semiconductor device is changed depending on the model as described above, for example, in order to mount the photodetector of the above example, the device having the semiconductor chip 2 ′ is aligned with the reference line (for example, the reference line 1 in the drawing). , 0 degree, 30
It must be rotated by 45 degrees and die-bonded.

In such a case, it is extremely complicated to adjust the angle of each individual device before mounting. Since the pellet size of the shikase device is not necessarily the same (for example, the size of the semiconductor chip 2'in FIGS. 8A and 8B is different from that in FIG. 8C), the installation direction and the pellet size are different. Different ones have to be individually set according to the model, which is extremely troublesome in production.

In order to avoid this, it is possible to configure the lead frame so that the device installation always has a fixed direction, but if this is done, the angle will be fixed and it will not be possible to mount it in other directions, so one model Only applicable to. Also, the pellet size of the device will be limited, and to use devices of different sizes,
In addition, another lead frame is required, and the problem cannot be solved.

The present invention makes it possible to perform the work easily and with versatility, even when various devices are mounted at various angular positions as described above, or when semiconductor chips of different sizes are used. For a specific angle, it is intended to provide a technique capable of always achieving accurate placement at that angle.

[Means for Solving Problems and Its Action] In order to solve the above problems, in the present invention, the structure of the lead frame used for mounting the semiconductor device is devised. That is, the lead frame of the present invention is
The die pad portion has a plurality of guide portions for mounting the semiconductor chip at two or more desired different angles with respect to the reference line of the die pad portion, and the guide portion includes the die pad. Corner that is the outline of the part,
Alternatively, it is formed by a side that is an outer shape of the die pad portion and that has a predetermined angle with respect to the reference line, and the die pad portion has a pair of leads in a pair of opposing portions thereof, The lead frame is characterized in that the guide portion is provided in another pair of facing portions that intersect with the pair of facing portions.

With the above configuration, when mounting the semiconductor chip on the die pad portion of the lead frame, the semiconductor chip is always mounted in a fixed direction if the semiconductor chip is placed in accordance with the guide portion provided on the die pad portion. . Also, since this guide part is provided in a plurality so as to indicate two or more different mounting directions, when it is used for a certain model, it is mounted according to one guide part indicating one mounting direction, When used for other models, it can be mounted according to the guide part showing the other mounting direction. In this way, the semiconductor chip can be mounted in any direction out of the mounting directions indicated by the guide portion, so that even a single lead frame is highly versatile. In addition, the semiconductor chip can be always mounted in a fixed direction indicated by the guide portion if it is aligned with the desired guide portion.

The structure of the present invention will be described below with reference to FIG. 1 showing an embodiment of the present invention which will be described in detail later.

The lead frame 1 of the present invention, as illustrated in FIG.
It has a die pad portion 11 on which a semiconductor chip is placed. On the peripheral portion of the die pad portion 11, guide portions 3, 4, 5 indicating the mounting direction of the semiconductor chip are provided, for example, as illustrated. The guide parts 3, 4, 5 indicate two or more mounting directions of different semiconductor chips, and accordingly, a plurality of guide parts are provided. For example, in the case of the illustrated example, the guide portion 3 (consisting of the guide portions 31 to 33) determines the mounting direction of the semiconductor chip in the direction of 0 degree with respect to the reference line 1. Guide part 4 (consisting of guide parts 41 to 44)
Defines the mounting direction of the semiconductor chip in the direction of 30 degrees with respect to the reference line 1. Guide part 5 (guide part 5
1, 52)) defines the mounting direction of the semiconductor chip in the direction of 45 degrees with respect to the reference line 1.

The operation of the present invention will be described in more detail by explaining the operation of the illustrated example.

When it is desired to mount the semiconductor chip 2 in a direction with an inclination of 0 degrees with respect to the reference line 1, the semiconductor chip 2 is placed in alignment with the guide portions 3 (31, 32, 33) of the die pad portion 11 as shown in FIG. Place it. As a result, as shown in FIG. 2, the semiconductor chip 2 is mounted in the direction of 0 degree with respect to the reference line 1. Specifically, the centers may be aligned and the sides of the semiconductor chip 2 may be parallel to the guide portions 31, 32, 33.

When it is desired to mount the semiconductor chip 2 in the direction of an inclination of 30 degrees with respect to the reference line 1, the semiconductor chip 2 is aligned with the guide portion 4 (41, 42, 43, 44) of the die pad portion 11 as shown in FIG. Place the chip 2. As a result, the semiconductor chip 1 is mounted in the direction of 30 degrees with respect to the reference line 1 as shown in FIG. Specifically, similarly to the above, with the centers aligned, the sides of the semiconductor chip 2 are connected to the guide portions 4 (41, 42, 4).
3, 44).

Further, when it is desired to mount the semiconductor chip 2 in a direction of 45 degrees with respect to the reference line 1, as shown in FIG.
The semiconductor chip 2 is mounted according to the guide portion 5 (51, 52) of 1. The semiconductor chip 1 is thereby mounted in the direction of 45 degrees with respect to the reference line 1 as shown in FIG. Match the centers and make the sides parallel to the guides.

Thus, by using the lead frame of the present invention, the semiconductor chip 2 can be mounted in a desired direction according to the guide portions 3, 4, 5. In addition, since the direction of the semiconductor chip 2 is always fixed if it is adjusted to a specific guide portion, the semiconductor chip 2 can be mounted with the necessary fixed directionality according to the model.

Further, the lead frame of the present invention has a structure in which the guide portion is formed by a corner portion or a side having a predetermined angle with respect to the reference line (reference numeral 3 shown in FIG. 1).
The corner-shaped guide portion 3 shown by reference numerals 1 and 32, the reference numeral 41,
Corner-shaped guide portion 4 indicated by 42, similarly reference numerals 51 and 52
(See the corner-shaped guide portion 5 and the side-shaped guide portion 3 indicated by reference numeral 33, and the side-shaped guide portions indicated by reference numerals 43 and 44). Each of the corners forming the guide portion or the side having a predetermined angle with respect to the reference line forms the outer shape of the die pad portion.

Further, the lead frame of the present invention has a pair of leads at a pair of opposing portions of the die pad portion (opposing portions which are diagonal portions at upper left and lower right of FIG. 1) as illustrated in FIG. The guide portions 3, 4 and 5 are provided at another pair of facing portions (upper right and lower left facing portions in FIG. 1) intersecting with the pair of facing portions.

Further, when carrying out the present invention, as is apparent from the above description, it is convenient that the reference position of the semiconductor chip is determined. Therefore, in a preferred embodiment of the present invention, the die pad portion has It has a structure in which a pattern indicating the reference position of the semiconductor chip is formed (see the description below).

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, a lead frame to which the present invention is applied is used in a CD photodetector package.

In particular, this embodiment is designed so that the mounting direction of the semiconductor chip can be changed according to the CD model when the pellet size of the semiconductor chip used for the photodetector is different.

If the present invention is not applied, for example, the photo detector is
If both the size of 8 × 1.0 and the size of 0.7 × 0.7 are to be mounted according to the locus of the CD pickup, the semiconductor chip 2'is set to the reference line as described with reference to FIG. (Eg l) 0 degree, 45
It must be rotated by 30 degrees and die-bonded.

However, in this embodiment, the present invention is applied and 0 is applied to the reference line l.
Since the guide portion 3 indicating the direction of 30 degrees, the guide portion 4 indicating the direction of 30 degrees, and the guide portion 5 indicating the direction of 45 degrees are provided, the semiconductor chip 2 can be easily mounted in the desired direction. It was

In the lead frame of the present embodiment, as shown in FIG. 1, the guide portion 3 has a guide portion 31 that is perpendicular to the reference line 1 and a guide portion 32 that is also parallel, and both guide portions 31 and 32 have corners. And a guide part 33 parallel to the reference line l.
To have. The guide portion 4 is the guide portion 31, 32.
Is a guide portion 4 that forms a corner inclined by 30 degrees with respect to the reference line l.
1 and 42, and also has guide portions 43 and 44 parallel to the guide portion 41. The guide portions 51 and 52 are orthogonal to each other and are formed to be inclined by 45 degrees with respect to the reference line l.

When the semiconductor chip 2 constituting the photodetector is placed in the direction of 0 degree with respect to the reference line l, the center of the semiconductor chip 2 is aligned with the center of the die pad portion 11 as shown in FIG. The side 21 or 22 of the above is parallel to the guide portion 31, and / or the side 23 or 24 is parallel to the guide portion 32 or 33. As a result, the semiconductor chip is mounted in the desired direction as shown in FIG.

When mounting the semiconductor chip 2 constituting the photodetector in the direction of 30 degrees with respect to the reference line 1, as shown in FIG. 3, the center of the semiconductor chip 2 is aligned with the center of the die pad portion 11 as described above. The side 21 or 22 of the semiconductor chip 2 is parallel to the guide portion 42, and / or the side 23.
Alternatively, 24 is parallel to the guide portion 41, 43 or 44. As a result, as shown in FIG. 3, the semiconductor chip 2 is mounted in a desired inclined direction of 30 degrees.

The examples shown in FIGS. 2 and 3 are for the case where the size of 0.8 × 1.0, that is, the rectangular semiconductor chip 2 is used. It is obvious that a semiconductor chip can be used, and FIG. 4 shows a case where the semiconductor chip 2 constituting the photodetector is mounted in a direction of 45 degrees with respect to the reference line || 2 is an example of using a square one as described above. Also in this case, as shown in FIG. 4, the center of the semiconductor chip 2 is located at the die pad portion 11
The side 25 or 26 of the semiconductor chip 2 is aligned with the center of
Is parallel to the guide portion 51 and / or the side 27 or 28 is parallel to the guide portion 52. As a result, as shown in FIG. 4, the semiconductor chip 2 is mounted in a desired inclined direction of 45 degrees. In this example, it will be apparent that the same is true even if the rectangular semiconductor chip 2 as used in FIGS. 2 and 3 is used.

In this way, as shown in FIGS. 2 to 4, one lead frame is used for each 0 degree and 30 degrees with respect to the reference line l.
FIGS. 8A to 8C collectively show that the semiconductor chip can be mounted at 45 degrees.

According to the present embodiment, the semiconductor chip 2 having an arbitrary size and shape can be mounted in a desired direction according to the guide portions 3, 4, 5, and if a fixed guide portion is fitted, the fixed direction can be always maintained. It can be secured.

In this embodiment, a mark indicating the center of the die pad portion 11 as shown by reference numerals 61 to 64 in FIG. A cross section of this mark is shown in FIG. In addition, the die pad 11
A circular groove 7 having the same center as the die pad portion 11.
Formed intermittently. This cross section is shown in FIG. The groove 7 and the marks 61 to 64 function as a pattern indicating the reference position of the semiconductor chip 2. By doing so, the die bond position (including the inclination direction determined by the guide portions 3, 4, 5) can be accurately obtained.
The marks 61 to 64 indicating the center position, the groove 7, and the inclinations of the guide portions 3, 4, and 5 are manufactured accurately with a predetermined package mold line so that the pickup can be performed even after the package is soldered to the substrate. The laser beam can be correctly received according to the movement locus of.

In addition, in this embodiment, as shown in FIG. 7, a recess 12 is formed in the lead frame 1 so as to suppress entry of moisture such as water. In addition, the narrow portion 13 (Fig. 1) is provided to ensure this.

As described above, according to this embodiment, even if the size (pallet size) of the semiconductor chip 2 is different or the mounting direction of the semiconductor chip 2 is different, desired mounting can be achieved according to each condition. . Moreover, if any one of the guide portions is fitted, the semiconductor chip 2 can be properly placed in a specific and fixed direction indicated by the guide portion.

In the present embodiment, as described above, the semiconductor chips 2 of two types (rectangle and square) can be used, and three types of guide portions 3, 4, and 5 are provided so that three types of die bond portions are possible. Since it is designed to be tightened, it is extremely effective in practice. It goes without saying that semiconductor chips having other appropriate shapes have general versatility, and various types of guide portions can be provided as necessary.

According to the present embodiment, the package structure as described above enables many devices to be die-bonded to the same package with various inclinations. In particular, here, the same lead frame is used for three types. Made possible Since this embodiment applies the present invention to a photodetector for CD, the position accuracy of the device is required to be high due to the nature of such a detector. For example, the X and Y directions are ± 0.1 mm and the angle θ direction is 2 degrees or less. As described above, the required accuracy is high, but this can be easily achieved by using the present invention.

Moreover, in this embodiment, since the position marks 61 to 64 are provided in particular, the accuracy can be checked easily, and the adjustment of the machine at the start of the die bonding can be extremely facilitated, and the trial and check can be easily performed.

In the case of using a semiconductor chip in which the pattern b is preliminarily inclined by 30 degrees or 45 degrees with respect to the sides of the pellet a as shown in FIG. Although unnecessary, this makes the pallet area larger than the pattern layout in which the pattern b is parallel to the side of the pellet a, making the pellet configuration difficult and lowering the device yield and reliability. , Leading to higher costs. Further, naturally, the effects of the present invention such as versatility for a large number of types of semiconductor chips and the ability to have a plurality of types of inclination in the mounting direction cannot be obtained. From this example, it will be clear that the present invention is excellent.

The present invention can be applied not only to a CD as in the above example, but also to those which take a signal from a disk such as a video disk, a laser disk or the like, and other semiconductor chips which have a specific directionality, and can be appropriately applied. Of course, the present invention has been described above,
It is not limited to the illustrated embodiment.

[Effect of device]

As described above, according to the present invention, the mounting direction of the semiconductor chip can be set to any direction by taking any one of the plurality of angles indicated by the guide unit. With this, it is possible to always mount at an accurate position. Moreover, even if the shape of the semiconductor chip is different, there is versatility. As a result, it is possible to easily achieve accurate placement while meeting various conditions.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the lead frame of the present invention. 2 to 4 are plan views showing the mounting state of the semiconductor chips in different directions by the guide portions. 5 is a sectional view taken along the line AA in FIG. 1, FIG. 6 is a sectional view taken along the line BB, and FIG. 7 is a sectional view taken along the line CC. 8 (a), (b) and (c) are diagrams for explaining the configuration of the above-described embodiment of the present invention and also for explaining the problems to be solved by the present invention. FIG. 9 is a drawing for explaining a comparative example. DESCRIPTION OF SYMBOLS 1 ... Lead frame, 11 ... Die pad part, 2 ... Semiconductor chip, 3-5, 31-33, 41-43, 51, 52
... Guide portions, 61 to 64 ... Marks (patterns indicating reference positions), 7 ... Grooves (patterns indicating reference positions).

Claims (1)

[Scope of utility model registration request] 1. A lead frame for a semiconductor device having a die pad portion for mounting a semiconductor chip, wherein the semiconductor chip is mounted at two or more desired different angles with respect to a reference line of the die pad portion. While having a plurality of guide portions in the peripheral portion of the die pad portion, the guide portion is a corner portion that is the outer shape of the die pad portion,
Alternatively, it is formed by a side that is an outer shape of the die pad portion and that has a predetermined angle with respect to the reference line, and the die pad portion has a pair of leads in a pair of opposing portions thereof, A lead frame for a semiconductor device, characterized in that the pair of opposing portions intersect with the pair of opposing portions, and the guide portions are provided at the other pair of opposing portions.