JPH077154U - Lead frame for semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lead frame for a semiconductor device in which no camber is generated and no camber adjustment time is required. [Construction] In products that require engraving on the outer frame of the lead frame, engrave the center of the outer frame of the lead frame so that camber does not occur on the lead frame.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a lead frame for a semiconductor device, and more particularly to a lead frame having an outer frame provided with a marking.

[0002]

[Prior art]

 In the manufacturing process of the lead frame, the outer frame is often provided with a stamp for classification of the lead frame type. Conventionally, the method of providing the marking on the outer frame of the lead frame varies depending on the designer.

That is, when the marking is provided only on one side of the outer frame, when the marking is provided outside the widthwise center of the outer frame, or when the marking is provided inside the widthwise center of the outer frame. There are various other cases such as the size of the marking and the depth of the marking.

However, when a marking is provided on the outer frame of the lead frame, camber often occurs due to the influence of the marking. The camber is the meandering of the long lead frame caused by the distortion that occurs in the outer frame of the lead frame. When camber occurs, the process such as transportation trouble (strap) or guide hole galling at the stage of mounting the completed IC. It causes a failure.

Therefore, as a method of engraving the marking on the outer frame, the shape, depth, direction, etc. of the engraving are taken into consideration. The current situation is to prevent the occurrence of.

[0006]

[Problems to be solved by the device]

 Since the camber may be given to the lead frame by giving the outer frame of the lead frame an extension strain by making the above-mentioned marking, the method of making the mark was examined. As a result, the following trends were revealed.

That is, (1) When the marking is provided on only one side of the outer frame, a camber is likely to occur in the lead frame.

(2) When a marking is made on only one side of the outer frame as in the case of (1) above, the size of the marking and the degree of camber generated vary depending on the depth.

(3) If the generated camber exceeds the product standard, it is necessary to correct the camber.

However, the necessity of marking on only one side of the outer frame and the size, shape, direction, etc. of the marking come from design requirements, and it is difficult to change each time for camber correction. is there. Moreover, even if the depth of the marking is to be adjusted, it is necessary to adjust the depth of the marking with an accuracy of a few microns, which makes it extremely difficult to adjust the marking die or carry out the marking operation.

In the case of the conventional engraving method, in order to prevent the occurrence of camber, it is necessary to consider the engraving method of both outer frames at the designing stage, and to put a pad on the opposite side of the engraving. It will be an extra burden. In addition, if camber occurs due to engraving, it will be necessary to adjust the camber by newly engraving it or adding a tatto, but in this case, it is the opposite of the case of the present invention described later. It can be said that the correction effect is great if a correction mark or a pad is added at a position other than the center position in the width direction of the frame.

[0012] The occurrence of camber due to the marking of the lead frame is remarkable especially in a thin plate material having a thickness of about 0.15 mm or less.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a lead frame for a semiconductor device in which no camber is generated and no camber adjustment time is required.

[0014]

[Means for Solving the Problems]

 The above object can be achieved by a lead frame for a semiconductor device of the present invention, that is, a lead frame having a mark at a specific position.

In the lead frame of the present invention, the marking is provided at the center of the outer frame of the lead frame in the width direction.

In the lead frame for a semiconductor device of the present invention, engraving is often done at the time of stamping by a progressive die, but engraving is done at other stamping steps and depress cutting steps. Is also possible.

[0017]

【Example】

 An embodiment of the present invention will be described with reference to FIG.

(Example) In this example, a frame having a width of 22.5 mm, a length of 198.0 mm, and a plate thickness of 0.15 mm was used.

As shown in FIG. 1, a marking was provided in the center of the outer frame of the lead frame in the width direction. In this case, it was confirmed that the marking did not affect the camber, and that the camber did not change even if the depth of the marking was changed. The markings were provided at the same time when the lead frame was punched out by the progressive die.

[0020]

[Effect of device]

 As described above, according to the lead frame for semiconductor device of the present invention having the engraved mark, (1) the camber adjustment time can be greatly reduced, the adjustment is virtually unnecessary, the production effect is improved, and the product yield is also increased. did.

(2) The change in camber due to the depth of marking is eliminated, and the product quality is stable.

[Brief description of drawings]

FIG. 1 is a plan view of an outer frame of a lead frame showing a marking position of the outer frame of the lead frame according to the present invention.

FIG. 2 is a plan view of a conventional lead frame having a conventional marking.

[Explanation of symbols]

 1 Marking position in the present invention 2 Conventional marking position

Claims (1)

[Scope of utility model registration request] 1. A lead frame for a semiconductor device, wherein an outer frame of a lead frame is provided with a marking, and the marking is provided at the center of the outer frame of the lead frame in the width direction.