JPS626655B2 - - Google Patents

Abstract

PURPOSE:To improve mounting precision, by holding a semiconductor pellet attached to a pickup tool of a mounting head by means of gauging arms provided on the outer surface of the tool and thereby positioning it, and mounting it on the adhesive-coated surface of a lead frame. CONSTITUTION:Mounting head 12 having vacuum-suction pickup tool 14, which is placed in the center of base 13 in such a manner that it can move up and down freely, is fitted to the end of rod 11, which can move back and forth in a straight line or move up and down. Gauging arms 16, which are supported by supporting shafts 15 and can rotate freely, are provided on the four sides of base 13. Tool 14 is made to make up-and-down motion by lever 22 which moves up and down about supporting shaft 12. Lower end 16a of arm 16 is opened or closed by positioning cam 28, and fixes up-and-down moving tool 14 for a specified time. By this, pellet 1 is sucked by tool 14, positioning is done by arm 16, and thereby it is placed on lead frame 5.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) The present invention relates to the production of micro parts such as semiconductor devices and surface wave devices. The present invention relates to an improvement in the method of mounting on a lower member.

(Prior Art) As shown in FIG. 1, in the conventional mounting method, an upper member is cut from a wafer and transferred to a pick-up position A using an XY direction moving table (not shown). The pellet 1a as shown in FIG. Mounting position C of stem or lead frame 5 as a member
The vehicle was then transported to and mounted.

In addition, as a conventional method that does not provide the above-mentioned positioning position B, as shown in FIG. There were some items that needed to be transported and mounted.

Furthermore, as described in Japanese Patent Application Laid-Open No. 104859/1983, there is an IC insertion mechanism in which a plurality of IC lead lowering guide members are provided around a vacuum suction section.

This IC insertion mechanism works until the tip of the IC lead begins to enter the lead insertion hole of the printed board.
A guide member for guiding the lowering of the lead is positioned in a closed position.

(Problems to be Solved by the Invention) However, such conventional methods have the following drawbacks.

First, the conventional first and second
In the case where the pick-up tools 2 and 4 are used, the position B for positioning the pellet 1 is provided separately, which makes the device complicated, and the first and second pick-up tools 2 and 4 are used twice to pick up the pellet 1.
Because it comes into contact with the patterned surface of the substrate, the patterned surface is often damaged, which is a cause of defects. In addition, in this method, the tip of the second pick-up tool 4 that conveys the pellet 1b after positioning is a flat surface, and if the indexing of the entire device is made faster, the holding position of the pellet 1b may shift due to inertia, and pick-up errors may occur. has occurred,
For pellets of large size, the positioning accuracy of the mounting relative to the stem or lead frame 5 was not good.

Note that, as in the conventional example shown in FIG.
A mechanism for positioning a pellet by holding it between a plurality of positioning members at a positioning position is described in Japanese Patent Application Laid-Open No. 49-29075, in which a semiconductor pellet is placed on a support member. , there is one in which the pellet is elastically positioned by positioning members on four sides that are elastically closed by tension springs.

Furthermore, in the conventional mounting method using the collet 6 shown in FIG. 2, since the pellet 1 is positioned by the tapered surface 7 inside the collet 6, the
-Au in the Si eutectic mount method, solder in the solder mount method, adhesive in the dispense method and stamping mount method, etc. may adhere to the tip of the collect 6, and such deposits will transport the next pellet 1. At that time, it adhered to the pellet 1, causing defects.
For example, empirically, when a pellet 1 with a thickness of t is adsorbed by the collet 6, the stem or lead frame 5
Therefore, the height to the tip of collet 6 is t/2,
There is a high possibility that the adhesive on the stem or lead frame 5 will adhere to the tip of the collet 6. Further, positioning using the collet 6 can be performed for square or rectangular shaped pellets 1, but cannot be performed for pellets shaped like a parallelogram, for example.

Note that, as in the conventional example shown in FIG.
As a pellet adsorption device,
As described in Japanese Patent Application Laid-Open No. 53-25368, the vertical movement of the ring body is adjusted by rotating the ring body that is threadedly engaged with the tip of the collet body. Adjust the width of the mouth of the gripping part made up of four metal pieces so that the width of the mouth of the gripping part matches the length of one side of the pellet, and then insert the pellet into the gripping part so that the metal piece holds the pellet. There are some that hold the pellets in place and at the same time suck the pellets into the concave part of the grip by vacuum suction from the suction hole, but in the grip of the collet shown in this publication, the spacing between the metal pieces is adjusted to match the pellet size. After being used, it is used in a fixed state and is not opened and closed for individual pellets, so the second
I have a similar problem to the one in the picture.

Furthermore, the IC insertion mechanism disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 53-104859 has a structure in which the IC leads descend while coming into contact with the guide member.
There is no problem because the lead is made of a hard metal and does not deform easily. However, if the lead is made of a material that is easily deformed, such as a pellet, a problem arises in that the lead deforms when descending.

The purpose of the present invention is to improve these various drawbacks, and to improve the mounting accuracy of the upper member to the lower member, and to reduce the risk of damage to the upper member by a pick-up tool. In addition, the device is simplified to facilitate its maintenance, and furthermore, it eliminates mistakes in the pick-up tool, increases the speed of the entire device, and eliminates the risk of deformation when pellets are lowered. .

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a mounting method in which an upper member 1, which is a member to be mounted, is mounted on the upper surface of a lower member 5. By raising the pick up tool 14, the upper member 1 is raised between the plurality of gauging arms 16 provided on the outer circumference of the pick up tool 14, and the plurality of gauging arms 16
is elastically closed by a spring 26 to sandwich and position the upper member 1.
is transferred to the mounting portion of the lower member 5 by moving the mounting head 12, the plurality of gauging arms 16 are opened, and the pick-up tool 14 is lowered to lower the upper member 1. The upper member 1 is mounted on the mounting portion of the member 5.

(Function) In the present invention, the pick-up tool 14 is lowered and the upper member 1 is attracted to the lower end of the pick-up tool 14 by vacuum force. Next, this upper member 1
The pick-up tool 14 is raised with the gauging arm 14 adsorbed, and the upper member 1 is pulled up between the lower ends 16a of the gauging arm 16, and the lower ends 16a are closed and positioned. Then, like this, upper member 1
Mounting position C while positioning
After transporting the gauging arm 16 to
By lowering the pick-up tool 14 and releasing the vacuum force, the upper member 1 is placed on the mounting portion of the lower member corresponding to the position C.
mounting.

(Example) An example of the present invention will be described based on FIGS. 3 to 5.

A mounting head 12 is attached to the tip of a rod 11 that is linearly advanced and retracted and horizontally moved up and down by a cam mechanism (not shown).

This mounting head 12 has a cylindrical pick-up tool 14 inserted into the center of the base 13 so as to be movable up and down, and gauging arms that are rotatable with support shafts 15 in the middle on each of the four sides of the base 13. 16 is fitted. Further, the pick-up tool 14 is provided below the roller 19 of the mounting plate 18 at the upper end, and is advanced and retracted through the operating section 20 by a cam mechanism (not shown) or the like, and is attached to a support shaft 21.
The mounting plate 18 may be driven upward by a lever 22 that is rotated vertically around the
Compression coil spring (not shown) in contact with the top surface of
The upper end of the pick-up tool 14 is connected to a vacuum hose 24 of a vacuum pressure source, and the lower end is formed flat. Furthermore, the gauging arms 16 at the four locations move the rollers 25 at each upper end to the base 13.
A compression coil spring 26 provided inside the base section 13 biases the inner peripheral cam surface of a ring-shaped positioning cam 28 rotatably held by rollers 27 at the four corners of the upper surface of the base section 13, and this positioning cam 28 Operation section 29
The positioning cam 28 is rotated by moving the positioning cam 28 forward and backward by a cam mechanism (not shown) to open and close the lower end portion 1a of each gauging arm 16.

Next, the operation of this embodiment will be explained.

The pellet 1 serving as the upper member is a pellet tray 31 or a cut wafer.
It is transported to pick-up position A by being placed on a Y-direction moving table (not shown). Here, the pick-up tool 14 is lowered, and the pellet 1 is adsorbed to the lower end of the pick-up tool 14 by the vacuum force of a vacuum pressure source (not shown). Next, with the pellet 1 adsorbed, the pick up tool 14 is raised, and the positioning cam 28 is rotated to position the pellet 1 so as to be enclosed in the gauging box 32 by the lower end 16a of the gauging arm 16. At this time, the external dimensions of the gauging box 32 are almost the same as those of the pellets 1, and when the gauging arm 16 is closed, its lower end 16a hits the side surface of the gauging box 32, so that excessive force is applied to the pellets 1. Never. Next, the rod 11 is moved and the pellet 1 is conveyed to the mounting position C while being positioned. After opening the gauging arm 16, the pick up tool 14 is lowered and the lead as the lower member corresponding to the position C is moved. The pellet 1 is pressed onto the adhesive coated surface of the frame 5 serving as the mounting portion to complete the mounting. In addition, Fig. 4 is a diagram of the above-mentioned action, and in this Fig. 4, a → b
→c→b→a completes one cycle from picking up to mounting.

Furthermore, by arbitrarily changing the shape of the inner circumferential cam surface of the ring-shaped positioning cam 28, for example, as shown in FIG. The four gauging arms should be driven in a certain order, such as by delaying the movement of the four gauging arms. By setting the drive order in this way,
Even when positioning a pellet 1c shaped like a parallelogram in the figure, the contact between the pellet 1c and the gauging arms 16x, 16y is smooth, allowing accurate positioning without applying excessive force to the pellet 1c. .

The present invention can be used not only in the structure of the semiconductor element or surface wave element, but also in a wide range of applications, such as when fixing the element to a liquid crystal or a printed wiring board.

〔Effect of the invention〕

According to the present invention, the upper member is sucked and raised by the pick-up tool of the mounting head, and then the upper member is clamped by a plurality of gauging arms provided on the outer periphery of the pick-up tool. Since the parts are positioned and then directly transferred to the mounting section of the lower part for mounting, there is no need for a positioning relay point like in the past, which improves the accuracy of mounting the upper part to the lower part. It is possible to reduce the risk of damage to the upper member due to the pick-up tool, and since a separate positioning device is not provided, the entire device has more space and is easier to maintain. In addition, since the upper member is held and positioned by multiple gauging arms on the outer periphery of the pick-up tool, it is possible to eliminate pick-up errors and speed up the entire device. The improved accuracy makes it possible to eliminate the need for a positioning device such as a wire bonder in a post-process, and it is possible to improve the quality of semiconductor elements and the like. The present invention further provides a method for transferring the upper member by moving the mounting head to the mounting portion of the lower member, opening the plurality of gauging arms, and lowering the upper member by lowering the pick-up tool. Since the upper member is mounted on the mounting portion of the side member, the upper member is lowered onto the lower member without any interference from the open gauging arm, and when lowered, the upper member is attached to the guide member, etc. There is no risk of deformation due to contact with. Further, in the present invention, after the upper member is raised between the plurality of gauging arms using a pick-up tool, the plurality of gauging arms are elastically closed by a spring to sandwich and position the upper member. Therefore, even if the upper member changes to a different size, the change can be automatically accommodated, and the upper member of various sizes can be used with the same gauging arm within the range that can be inserted between the plurality of gauging arms. It has the advantage of being able to be positioned using an arm, and the positioning range is extremely wide.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional mounting device.
FIG. 2 is a longitudinal cross-sectional view of a collet used in the conventional mounting method, FIG. 3 is a perspective view showing an embodiment of the mounting method of the present invention, and FIG. 4 is a cross-sectional view showing its operation.
FIG. 5 is an explanatory view of the bottom. DESCRIPTION OF SYMBOLS 1... Pellet as an upper member, 5... Lead frame as a lower member, 12... Mounting head, 14... Pick up tool, 16... Gauging arm, 26... Spring.

Claims (1)

[Claims] 1 In a mounting method in which an upper member, which is a member to be mounted, is mounted on the upper surface of a lower member, the upper member is adsorbed by a pick-up tool of the mounting head, and by raising the pick-up tool, the outer periphery of the pick-up tool is removed. The upper member is raised between a plurality of gauging arms provided in the mounting head, and the plurality of gauging arms are elastically closed by springs to sandwich and position the upper member, and the upper member is attached to the mounting head. is moved to the mounting section of the lower member, the plurality of gauging arms are opened, the pick-up tool is lowered to lower the upper member, and the upper member is mounted on the mounting section of the lower member. This mounting method is characterized by the fact that the