JPH04363668A - Manufacture of semiconductor acceleration sensor - Google Patents

Abstract

PURPOSE:To manufacture a semiconductor acceleration sensor wherein the position accuracy of the support part of an acceleration sensor chip is uniformized and the accuracy of characteristics is enhanced. CONSTITUTION:Leads 6 are arranged on the first frame 9a of a base frame 9 and the fixed end 1a and free end 1b of an acceleration chip 1 are respectively positioned and arranged on the second and third frames 9b, 9c of the base frame 9. The fixed end 1a, a part of the leads 6 and the first and second frames 9a, 9b are sealed with a resin to form a support block 10 and the part other than the resin sealed parts of the base frame 9 is cut off.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor acceleration sensor, and more particularly to a method of manufacturing a fixed support portion of an acceleration sensor chip.

0002

5 and 6 show a semiconductor acceleration sensor produced by a conventional manufacturing method. FIG. 5 is a cross-sectional view showing the overall structure, and FIG. 6 is a perspective view showing the state with the package cover removed. be. In the figure, 1 is the fixed end 1
The acceleration sensor chip has a free end 1b and a diaphragm region 1c on the fixed end 1a side. Reference numeral 2 denotes a strain gauge resistor disposed in the diaphragm region 1c of the acceleration sensor chip 1, which is connected and wired in a bridge shape. 3 is the electrode pad of the bridge of the strain gauge resistor 2, 4 is the package base, and 5 is the fixed end 1 of the acceleration sensor chip 1.
a pedestal supporting and fixing to the package base 4; 6 a lead provided through the package base 4; 7 a wire connecting the lead 6 and the electrode pad 3; 8 a wire placed on the package base 4; This is a package cover that covers each of the above components.

When acceleration is applied to the acceleration sensor chip 1 of the conventional acceleration sensor configured as described above, stress concentrates on the diaphragm region 1c, and the resistance of the strain gauge resistor 2 disposed on the diaphragm region 1c increases. Since the value changes, the bridge output changes depending on the magnitude of acceleration. If this bridge output is taken out to the outside via the electrode pad 3, wire 7, and lead 6, the acceleration value can be measured.

0004

[Problems to be Solved by the Invention] Since the semiconductor acceleration sensor manufactured by the conventional manufacturing method is constructed as described above, the characteristics change variously due to variations in the accuracy of the bonding position between the acceleration sensor chip 1 and the pedestal 5, resulting in poor performance. There was a problem above.

The present invention has been made to solve the above-mentioned problems, and provides a method for manufacturing a semiconductor acceleration sensor that can uniformize the positional accuracy of the support part of the acceleration sensor chip and improve the accuracy of the characteristics. The purpose is to

[0006]

[Means for Solving the Problems] A method for manufacturing a semiconductor acceleration sensor according to the present invention includes a base frame in which first, second, and third frames are formed at predetermined intervals across the longitudinal direction. , the fixed end of the acceleration sensor chip is placed on the first frame, the fixed end of the acceleration sensor chip is placed on the second frame, and the fixed end of the acceleration sensor chip is placed on the third frame, with each end placed together. a part of the fixed end side of the acceleration sensor chip not including the first frame of the lead and the fixed end of the acceleration sensor chip are sealed with resin together with the second frame; The method includes at least a step of forming a support block and a step of cutting off the underframe leaving a portion where the support block is sealed.

[0007]

[Operation] The underframe in the method for manufacturing a semiconductor acceleration sensor in this invention serves as a positioning frame when forming a support block,
After forming the support block, unnecessary parts are cut away.

[0008]

【Example】

Example 1. Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are a front view and a perspective view showing a part of the manufacturing process of a method for manufacturing a semiconductor acceleration sensor in Example 1 of the present invention, and FIG. 3 is a semiconductor acceleration sensor manufactured through the steps shown in FIGS. 1 and 2. It is a perspective view showing a sensor. In the figure, reference numeral 9 denotes an underframe in which first, second and third frames 9a, 9b, 9c are formed at predetermined intervals across the longitudinal direction. First, the fixed end 1a, the free end 1b and It has a diaphragm region 1c and a strain gauge resistor 2 on its surface.
and an acceleration sensor chip 1 with electrode pads 3 arranged thereon.
and the lead 6 are connected by a wire 7.

Next, the lead 6 is placed on the first frame 9a of the underframe 9, the fixed end 1a of the acceleration sensor chip 1 is placed on the second frame 9b, and the fixed end 1a of the acceleration sensor chip 1 is placed on the third frame 9b. The free ends 1b of the acceleration sensor chips 1 are placed on the frame 9c with their ends aligned. In this state, the positional relationship between the acceleration sensor chip 1 and the underframe 9 is set uniformly in any combination.

Then, a casting mold (not shown) is positioned with respect to this frame 9, and the fixed end 1a of the acceleration sensor chip 1, the electrode pad 3, a part of the lead 6,
The wire 7 and the first and second frames 9a and 9b are covered and molded resin is injected for sealing. Next, all parts of the underframe 9 other than the part sealed with the mold resin, that is, the parts exposed to the outside, are removed to complete the main part of the semiconductor acceleration sensor as shown in the third figure. And the support block 10
Since the acceleration sensor chip 1 and the acceleration sensor chip 1 are integrally cast, there is no possibility that the positional accuracy will vary depending on the combination, as is the case with the adhesion between the acceleration sensor chip 1 and the pedestal 5 in the conventional device shown in FIG. uniformly formed.

Example 2. In the first embodiment, the leads 6 are rod-shaped and placed on the first frame 9a, and then sealed with molded resin. However, as shown in FIG. Lead 11 when forming frame 9
If this is formed on the first frame 9a, the troublesome work of placing the unstable rod-shaped lead 6 on the first frame 9a during assembly can be omitted, and the workability is further improved.

0012

As described above, according to the present invention, on the first frame of the underframe in which the first, second and third frames are formed at predetermined intervals across the longitudinal direction, , the fixed end of the acceleration sensor chip is placed on the second frame with their respective ends aligned, and the free end of the acceleration sensor chip is placed on the third frame with their respective ends aligned. and a step of sealing a part of the fixed end side of the acceleration sensor chip and the fixed end of the acceleration sensor chip, which does not include the first frame of the lead, with a resin together with the second frame to form a support block. and a step of cutting out the underframe leaving behind the support block sealing portion, and since the leads are formed integrally with the first frame in advance, the positional accuracy of the support portion of the acceleration sensor chip is improved. It is possible to provide a method for manufacturing a semiconductor acceleration sensor that can make the characteristics uniform and improve the accuracy of characteristics and workability.

[Brief explanation of drawings]

FIG. 1 is a front view showing a part of the manufacturing process of a method for manufacturing a semiconductor acceleration sensor in Example 1 of the present invention.

FIG. 2 is a perspective view showing the manufacturing process in FIG. 1.

FIG. 3 is a perspective view showing a semiconductor acceleration sensor manufactured by the method for manufacturing a semiconductor acceleration sensor in Example 1 of the present invention.

FIG. 4 is a perspective view showing a part of the manufacturing process of a method for manufacturing a semiconductor acceleration sensor in Example 2 of the present invention.

FIG. 5 is a cross-sectional view showing a semiconductor acceleration sensor manufactured by a conventional manufacturing method.

FIG. 6 is a perspective view showing the semiconductor acceleration sensor in FIG. 5 with a package cover removed.

[Explanation of symbols]

1 Acceleration sensor chip 1a Fixed end 1b Free end 6. Lead 9 Underframe 9a First frame 9b Second frame 9c 3rd frame 10 Support block 11 Lead

Claims (2)

[Claims] 1. An underframe in which first, second and third frames are formed at predetermined intervals across the longitudinal direction, a lead is placed on the first frame, and a lead is placed on the second frame. placing the fixed end of the acceleration sensor chip on the third frame with their respective ends aligned; and placing the free end of the acceleration sensor chip on the third frame with their respective ends aligned; forming a support block that does not include the first frame and seals a part of the fixed end side of the acceleration sensor chip and the fixed end of the acceleration sensor chip with resin together with the second frame; A method for manufacturing a semiconductor acceleration sensor, comprising at least the step of cutting off the underframe leaving behind the support block sealing portion. 2. The method of manufacturing a semiconductor acceleration sensor according to claim 1, wherein the lead is integrally formed with the first frame of the underframe.