Bonding tool with shock absorbing device

Abstract

The invention provides a bonding tool with a shock absorbing device, which is provided with a spring A and a spring B which are connected in series in the vertical direction and have elastic coefficients of K. A balancing weight is connected between the spring A and the spring B. A bonding head is connected below the spring B. A chip can be picked up or released below the bonding head. And one side or two sides of the bonding head are connected to the bonding track in a sliding manner. Preferably, the balancing weights are shock absorbers with the same mass and the same height as the balancing weights in a free state. When the bonding head picks up the chip or bonds the chip, the impact force on the bottom chip is reduced, the rebound of the bonding head is reduced, and the purpose of protecting the chip is achieved.

Description

Technical Field

[0001] The present application relates to a bonding technology for micro components in the electronics industry. Background Art

[0002] The potential energy of an object due to elastic deformation and the interaction of elastic forces between its parts is called "elastic potential energy". For example, compressed gas, a bent bow, a wound spring, and a stretched or compressed spring all have elastic potential energy.

[0003] Elastic potential energy is the potential mechanical energy stored in the structure of a material or physical system because work is performed to distort its volume or shape. Elastic energy occurs when compression and stretching or deformation in any way is required. The greater the deformation of the same elastic object within a certain range, the greater the elastic potential energy it has, and vice versa. Springs are used in traditional bonding equipment.

[0004] When the bonding tool picks up the cut chip from the wafer, the high-speed descending bonding head will not only rebound when it contacts the chip, but may also cause undesirable situations such as chip surface damage. Therefore, it is necessary to adopt means to reduce impact contact, such as changing the design of the bonding equipment to reduce the above problems.

[0005] The invention of application number: 2020114353589 provides a method and tooling for hot-press bonding of MEMS devices with vibration reduction function, the method comprising: 1) fixing a carrier support plate on a tooling bottom plate; 2) placing a carrier on a carrier support plate; 3) placing a carrier pressure plate on the carrier; 4) placing a carrier metal leg pressure plate on the carrier pressure plate to shape the metal legs of the carrier; 5) taking out the shaped carrier; 6) fixing a sensor sensitive structure on a tooling bottom plate; 7) performing ball planting on the sensor sensitive structure; 8) performing piercing on the gold ball; 9) aligning the shaped carrier with the flat top gold ball; 10) performing hot-press bonding. This invention has many parts and a complex process. Summary of the invention

[0006] Purpose of the invention: Provided is a bonding tool with a shock-absorbing device which has little impact on a chip and has a buffering effect.

[0007] Technical solution: Traditional bonding tools usually use a load spring with a bonding head connected to the lower end. The bonding head moves back and forth on a vertical track: pick up the chip, move down, release the chip, heat and bond, move up, pick up the chip again, and so on. The bonding head has a connected counterweight (or a partially detachable component, which can be located at the top, middle or bottom of the bonding head).

[0008] The bonding tool with a damping device of the present invention replaces a commonly used load spring (elastic coefficient is K, and the spring free state length is L) with two springs A and spring B connected in series in the vertical direction, both with elastic coefficients K, a counterweight is connected between spring A and spring B (the sum of the free state length of spring A and the free state length of spring B is the same as the free length of the original load spring), and a bonding head minus the counterweight is connected below spring B. The bonding head can pick up or release a chip (or other microelectronic components) below.

[0009] One or both sides of the bond head are slidably connected to the bond track. Assume that the weight of the bond head is G, (the weight of the chip is very light and can be ignored, and the spring is a light spring and its mass is also negligible).

[0010] Preferably, the counterweight is an elastic shock absorber with the same mass and the same height in the free state, that is, it can be elastically deformed. The shock absorber is a block of spring or elastic material, preferably a polymer elastic material, and its elastic coefficient is greater than K, so that it has a greater elastic potential energy than the above spring when subjected to the same stretching or compression.

[0011] According to the law of conservation of energy, the sum of the kinetic energy of the bond head (including the counterweight), the gravitational potential energy, and the elastic potential energy of the spring is constant. Assuming that the gravitational potential energy of the bond head (including the counterweight) is zero at the lowest position (i.e. when bonding the chip), the sum of the kinetic energy of the bond head (including the counterweight) and the elastic potential energy of the spring is constant.

[0012] When the counterweight block is separated from the bonding head and moved upward between the two springs, the gravitational potential energy of the bonding head (excluding the counterweight block) is zero when it is in the lowest position; since the elastic potential energies of the two springs are basically the same, the gravitational potential energy of the counterweight block becomes larger, and the kinetic energy of the bonding head (excluding the counterweight block) will decrease. When the bonding head descends to the bottom for bonding, the impact force on the chip will be effectively alleviated, thereby achieving the expected shock absorption effect and providing better protection for the chip.

[0013] When the counterweight is replaced with a shock absorber and moved up between the two springs, the gravitational potential energy of the bonding head (excluding the shock absorber) is zero when it is in the lowest position; since the elastic potential energies of the two springs are basically the same, the gravitational potential energy of the shock absorber becomes larger, and the shock absorber is pulled by the upper and lower springs, elastic deformation will occur, and its elastic potential energy is greater than the elastic potential energy of springs of the same length. The kinetic energy of the bonding head (excluding the counterweight) will be reduced more, and when the bonding head descends to the bottom for bonding, its impact force on the chip will be significantly reduced, thereby achieving an efficient shock absorption effect and providing better protection for the chip.

[0014] Beneficial effects of the present invention: The present invention reduces the impact force on the bottom chip (substrate or lead frame) when the bonding head picks up the chip or bonds the chip, and reduces the rebound force of the bonding head, thereby achieving the purpose of protecting the chip.

[0015] By adjusting the weight or height of the counterweight block and the elastic coefficient of the shock absorber, a bonding tool with a corresponding vibration reduction effect can be obtained according to design requirements.

[0016] The invention is suitable for use in the picking up or bonding process of various chips or components in semiconductor manufacturing equipment, has low manufacturing cost, and is easy to use and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of a traditional bonding tool; Figure 2 It is a structural schematic diagram of a bonding tool of the present invention; Figure 3 is a schematic structural diagram of another bonding tool of the present invention; Figure 4 4(1) is a schematic diagram of the vibration process of the bonding head after the counterweight block is moved upward; 4(2) is a schematic diagram of the vibration process of the bonding head after the shock absorber is used and moved upward, the amplitude is reduced, and the number of oscillations is reduced.

[0018] In the figure: 1- load spring (1A- spring A; 1B- spring B); 2- bonding head; 3- chip; 4- track; 12- counterweight block; 13- shock absorber. DETAILED DESCRIPTION

[0019] Embodiment 1: like Figure 1 In the conventional bonding tool shown, the bonding head 2 has a connected counterweight 12, one side or both sides of the bonding head 2 are slidably connected to the bonding track 4, the bottom of the bonding head 2 can pick up or release the chip 3, and the bonding head 2 and the counterweight 12 are connected together or separately.

[0020] When this structure is applied to this application, it is transformed, such as Figure 2 As shown, a spring 1 is changed into two springs A [1A] and spring B [1B] which are connected in series in the vertical direction and have the same elastic coefficient K, a counterweight block 12 is connected between spring A [1A] and spring B [1B], and a bonding head 2 is connected below spring B [1B].

[0021] Embodiment 2: like Figure 3The bonding tool with a shock absorbing device shown in the figure has a bonding head 2, one side or both sides of the bonding head 2 are slidably connected to the bonding track 4, the bottom of the bonding head 2 can pick up or release the chip 3, and the bonding head 2 is connected to the counterweight block 12 together or separately; it also has two springs A [1A] and spring B [1B] with elastic coefficients K connected in series in the vertical direction, an elastic shock absorber 13 with an elastic coefficient greater than the above-mentioned springs [1A, 1B] is connected between the spring A [1A] and the spring B [1B], and the bonding head 2 is connected below the spring B [1B].

Claims

1. A bonding tool with a damping device, comprising a bonding head (2), one side or both sides of the bonding head (2) being slidably connected to a bonding track (4), the bottom of the bonding head (2) being capable of picking up or releasing a chip (3), and the bonding head (2) and a counterweight (12) being capable of being separated or connected together; characterized in that: There are also two springs A (1A) and spring B (1B) connected in series in the vertical direction, both with elastic coefficients K. A counterweight block (12) is connected between the springs A (1A) and B (1B), and a key head (2) is connected below the spring B (1B).

2. The bonding tool with a shock absorbing device according to claim 1, characterized in that: The counterweight (12) is an elastic shock absorber (13) having the same mass and the same height in a free state.

3. The bonding tool with a shock absorbing device according to claim 1, characterized in that: The elastic coefficient of the shock absorber (13) is greater than the elastic coefficient of the springs (1A, 1B).

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