JPH01262115A - Injection molding die for sealing ic - Google Patents

Abstract

PURPOSE:To seal an IC by a thermoplastic resin by projecting sliding pins, which are set into an upper cavity and a lower cavity and can be projected and retreated at specified strokes, only by the quantity of setting by resilient force and holding an inserted IC chip by the sliding pins under the state in which a die is closed. CONSTITUTION:An IC chip 1 is held by sliding pins 2 projected by springs 4 from the top force 6 side and sliding pins 3 projected by springs 4 from the bottom force 5 side, and the position of an attitude is fixed in the space of a cavity 11. When the inside of the cavity 11 is filled with a molten sealing medium through a sprue 10 and filling pressuring force is applied, the sliding pins 2 and the sliding pins 3 are pushed in. The IC chip 1 is maintained by the sliding pins 2 and the sliding pins 3 during a time when filling applied force is applied.

Description

[Detailed Description of the Invention] [Industrial Application Field 1] The present invention is directed to the use of thermoplastic resins in the semiconductor manufacturing process.
This invention relates to an injection mold for C sealing.

[Conventional technology 1] The progress of the semiconductor industry has been remarkable in recent years. One of the core elements of the semiconductor industry is IC manufacturing. Conventionally, thermosetting resins and ceramics have been used for most IC encapsulation in the IC manufacturing process, and injection molding encapsulation using thermoplastic resins has been limited to discrete devices such as diodes.

[Problem to be solved by the invention] The main reason for this is the high flow viscosity of the resin, and in the case of thermosetting resin transfer molding, the flow internal pressure at the time of sealing is 50
kg/cm", but in injection molding using thermoplastic resin, even if a resin with low viscosity is selected, the internal flow pressure will be 150 to 2.
00kg/cm" is required.

As a result, the posture of the inserted IC chip is disturbed due to the internal pressure of the flow, which further leads to breakage of the bonded lead wires.

[Means for Solving the Problems] In order to solve the above problems, the injection mold for IC sealing of the present invention has slide pins or slide pieces that are set in the upper cavity and the lower cavity and can move in and out at a predetermined stroke. The injection mold for IC sealing described above is characterized in that the inserted IC chip is ejected by a set amount by spring force or air pressure and is sandwiched between the slide pins or slide pieces with the mold closed. When the mold is closed and the inserted IC chip is sandwiched, the operating force of the slide pin or slide piece built into the upper cavity side or the lower cavity side is incorporated into the lower cavity side or the upper cavity side, respectively. The operating force is in the range of 1.1 to 3 times the operating force of the slide pin or slide piece.

[Example 1] Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a partial longitudinal sectional view of an injection molding mold for IC sealing of the present invention, and FIG. 1 is sandwiched between a slide pin 2 projected by a spring 4 from the upper mold 6 side and a slide pin 3 projected by a spring 4 from the lower mold 5 side, and its posture and position are fixed within the space of the cavity 11. When the molten sealing material is filled into the cavity 11 through the sprue 10 and a filling pressure is applied, the slide pins 2 and 3 are pushed in as shown in FIG. Until the filling pressure is applied, the IC chip 1 is held by the slide pins 2 and 3.
IC chip 1 is held by the fluid pressure during filling.
In the example shown in FIG. 1, there is a circuit pattern on the bonding side of the IC chip 1, so the slide pin 2 holds the IC chip 1 through the bonded lead wire 9. It's Nishide.

However, if the protruding forces of the slide pins 2 and 3 are equal, the position and posture of the inserted IC chip 1 will be slightly unstable. Therefore, as shown in FIG. By making the force 1°1 to 3 times stronger than the pushing force of the spring 12, even if the IC chip 1 is caught between the slide pins 2 and 3 due to mold clamping, the slide pin 3 will not be pushed into the lower mold side. Since the slide pin 2 is pushed into the upper mold side, the attitude and position of the IC chip 1 within the cavity 11 is completely determined. If the force of the spring 4 is too strong, the IC chip 1 will be destroyed when the filling force is applied.

FIGS. 4 and 5 show other embodiments of the present invention. Slide frame 13. A slide piece 14 is moved via a piston 16 driven by air pressure that enters and exits at a certain time from an air passage 15, and pinches the IC chip I.
Maintain the posture position of C-chip l.

〔Effect of the invention〕

As described above, according to the injection mold for IC sealing of the present invention, the posture and position of the IC chip is controlled within the cavity at the time when the molten resin is filled into the cavity.
Chips do not lose their posture even when using thermoplastic resin with high viscosity (can be sealed with uniform wall thickness and lead wires do not break.In recent years, IC devices have been required to become smaller and smaller, and the thickness of the package has increased. The injection mold for IC sealing of the present invention has lower manufacturing costs than current thermosetting plastic packages. It is possible to manufacture thermoplastic IC packages with low cost and high reliability.

[Brief explanation of the drawing]

FIG. 1 shows a partial vertical cross-sectional view of an injection mold for IC sealing according to the present invention, and FIG. 2 shows a partial vertical cross-sectional view of the mold shown in FIG. 1 after filling the cavity with resin. Figure 3 shows the case where the pushing force of the spring 4 built into the lower mold side is made stronger than the pushing force of the spring 12 built into the upper mold side in the injection molding mold for C sealing of the present invention. It is a partial vertical cross-sectional view. 4 and 5 are front views of partial longitudinal sections of other embodiments of the present invention, and FIG. 4 is a side view of FIG. 3. 1...IC chip 2...Slide pin 3...Slide pin 4...Spring 5...Lower die 6...Upper die 7...Eject turbine 8...Film 9... Lead wire 10... Sprue 11... Cavity 12... Spring 13... Slide piece 14... Slide piece 15... Air passage 16... Piston 17... Packing 18...・Lead frame 19...Bonding wire and above Applicant Seiko Epson Co., Ltd. agent Patent attorney Kisanbe Meiki (and 1 other person) Preliminary 1 Technician Z1 Koji 30 layers lf-G

Claims (2)

[Claims] (1) A state in which the slide pin or slide piece set in the upper cavity and lower cavity, which can move in and out for a predetermined stroke, is pushed out by a set amount by spring force or air pressure, and the inserted IC chip closes the mold. An injection mold for IC sealing, characterized in that the mold is sandwiched between the slide pin or the slide piece. (2) In the injection mold for IC sealing, the operating force of the slide pin or slide piece built into the upper cavity side or the lower cavity side when the mold is closed and the inserted IC chip is sandwiched. The injection for IC sealing according to claim 1, wherein the operating force of the slide pin or slide piece incorporated in the lower cavity side or the upper cavity side is in the range of 1.1 to 3 times, respectively. Molding mold.