JP2006134917A - Method of sealing with resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of sealing with a resin including the steps of regulating and supplying the amount of a sealing resin to be supplied to a work in which a plurality of semiconductor chips are laminated on a substrate according to the laminated state of the semiconductor chips. <P>SOLUTION: The method of sealing with the resin includes a step of keeping the volume in memory relative to the amount of resin supplementation of the semiconductor chip 2; a step of measuring a Z-axis height from the substrate side of the semiconductor chip 2 laminated on a work W to the chip of the uppermost side; a step of judging the amount of the chip laminations from the Z-axis height measurement value, and calculating the amount of resin or the amount of the resin supplemented to the semiconductor chip 2 running short or the amount of the resin which is not supplemented; a step of directing the amount of the resin supplemented or the amount of the resin not supplemented as control data to a resin supply unit 6; and a step of accumulating the control data on every work W and supplying the sealing resin from the resin supply unit 6 to the work W. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin sealing method in which a sealing resin is supplied to a workpiece in which a semiconductor chip is laminated on a substrate, and is clamped with a molding die to be resin-sealed.

  A CSP (Chip / Size / Package or Chip / Scale / Package) called a stacked package is used as a device such as an SRAM or a flash memory of a personal computer or a mobile phone. This is a semiconductor device of a type in which a plurality of semiconductor chips (for example, about 10 layers) are stacked and mounted on a substrate mounting area approximately the size of the semiconductor chip.

  Since the semiconductor device is a device that is complicated to assemble, due to poor stacking of semiconductor chips, poor wire bonding connection, or the like, for example, when 10 layers are stacked on a substrate, a failure occurs in the sixth layer, and more semiconductors. Chips are often not stacked. Therefore, when a semiconductor chip is laminated on a substrate in a matrix shape or a map shape and a work placed respectively is sealed with a resin, not all semiconductor chips are laminated (for example, 10 layers). The amount of resin required for sealing is different.

When resin-sealing a workpiece in which semiconductor chips are stacked on the substrate, the amount of resin loaded in the pot is quantitative in resin sealing by transfer molding, so that the resin corresponding to the missing portion of the semiconductor chip Cannot be sealed. In addition, in the compression molding method, it can be assumed that the liquid resin is increased and dropped in anticipation of chipping of the semiconductor chip, but the number of chipped semiconductor chips is not constant. For this reason, it is necessary to work to compensate the defective portion with the dummy chip so as to optimize the amount of resin. However, if a mechanism for supplying the dummy chip within the range of 10 layers is provided, a great cost is required.
Since a stacked semiconductor device is an expensive and sophisticated device, in order to improve the yield and reduce the manufacturing cost, it is necessary to securely seal in a resin sealing process. For this reason, it is possible to detect the lamination state of the semiconductor chip and increase the amount of resin by the amount of loss and perform compression molding with a uniform resin pressure, or in the case of individual cavities, the resin is not supplied to the defective portion of the semiconductor chip. It is desirable that the amount of resin can be adjusted by the workpiece so that sealing can be performed.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a resin sealing method in which the amount of sealing resin supplied to a work in which a plurality of semiconductor chips are stacked on a substrate is adjusted according to the stacked state of the semiconductor chips. It is to provide.

In order to achieve the above object, the present invention comprises the following arrangement.
That is, in a resin sealing method in which a work in which a semiconductor chip is laminated on a substrate is carried into a mold and compression-molded, a step of storing the volume of the semiconductor chip in correspondence with a resin filling amount, and a lamination on the work. The step of measuring the Z-axis height from the substrate surface to the uppermost chip among the semiconductor chips, and determining the chip stacking amount from the Z-axis height measurement value, or the amount of resin to be compensated for the insufficient semiconductor chip or not compensated The step of calculating the amount of resin, the step of instructing the resin supply unit as the amount of resin to be compensated or the amount of resin not to be supplied, and the control data are integrated for each workpiece to supply the sealing resin from the resin supply unit to the workpiece Including the step of:
Further, the resin compensation amount is characterized in that a resin amount corresponding to a lacking semiconductor chip volume is calculated.
The chip stack height of the workpiece is characterized in that the Z-axis height is measured using an image taken by an imaging apparatus using a Z-axis inspection machine.

  If the resin sealing method according to the present invention is used, the stacking height of the chip of the work in which the semiconductor chip is stacked on the substrate is measured, the chip stacking amount is determined from the height measurement value, and the missing semiconductor chip is compensated. The amount of resin to be used or the amount of resin that is not to be supplied is calculated, and after confirming good and defective products, resin sealing of the good products is ensured to prevent molding defects of expensive devices and to prevent waste of the sealing resin. Can be drunk. Therefore, the yield of expensive molded products can be improved.

  Hereinafter, preferred embodiments of a resin sealing method according to the present invention will be described in detail with reference to the accompanying drawings. This invention demonstrates the resin sealing method which adjusts and adjusts the amount of liquid resin supplied to the workpiece | work with which the semiconductor chip was laminated | stacked on the board | substrate as an example.

First, a schematic configuration of the resin sealing device will be described.
A liquid resin 6c is applied to the workpiece W supplied from the workpiece supply unit from a dispenser nozzle 6b provided in the resin supply unit 6 (see FIG. 1) (see FIGS. 3C and 3D). The liquid resin 6c may be applied outside the mold, or may be applied inside the mold. The workpiece W coated with the liquid resin 6c is clamped by a mold and subjected to compression molding. As the workpiece W, as shown in FIGS. 3A and 3B, a plurality of semiconductor chips 2 stacked on one surface of the substrate 1 and arranged in a matrix or a map are used. On the other surface of the substrate 1, terminal portions (for example, solder balls) 1 a are provided. The semiconductor chip 2 may be connected to the substrate 1 by wire bonding, or the chips may be connected to each other by flip chip. Further, a spacer 3 may be provided between the semiconductor chips 2 (see FIG. 3B).

Here, the configuration of the control system of the resin supply unit will be described with reference to FIG. The control unit 4 includes a CPU 4 a that outputs a control command to the resin supply unit 6 based on input data input from the Z-axis inspection machine 5, a ROM 4 b that stores an operation program for the dispenser nozzle 6 b, and storage of input data. And a RAM 4c used as a work area for the CPU 4a. The RAM 4c stores resin amount data to be supplemented (or not supplemented) with Z-axis height data and volume data for each semiconductor chip.
The control unit 4 receives Z-axis height data of the semiconductor chip 2 from the Z-axis inspection machine 5. The control unit 4 calculates resin amount data to be supplied according to the Z-axis height data input from the Z-axis inspection machine 5 and sends a control command to the resin supply unit 6.

Next, an example of a resin sealing method will be described with reference to FIG.
First, prior to compression molding, the Z-axis height position for each layer of the workpiece W to be resin-sealed is measured as Z-axis height data. The Z-axis height data of the workpiece W will be described assuming that the semiconductor chip 2 has six layers. Z0 indicates the height of the substrate 1 serving as the reference plane (measurement points Xi, Yi), and is a value (for example, Z0 = 0.064 mm) which is the height of the chip bottom surface near the chip. Note that Z0 is preferably measured every time in consideration of warping of the base slope 1. For example, in the case of six layers, the height data of each layer semiconductor chip 2 is given by Z1 = 0.15 mm to Z6 = 0.75 mm. Resin amount data necessary for sealing each layer semiconductor chip 2, for example, Vz1 = 0.00524cc to Vz6 = 0.00274cc, is stored in the control unit 4 of the resin supply unit in advance. This resin amount data is created based on the volume of each layer semiconductor chip occupying a mold cavity (not shown) (step S1).

  Next, the Z-axis height of the workpiece W is measured using the Z-axis inspection machine 5. In the measurement, the height to the chip upper surface Zc is measured at the central portion (measurement points Xj, Yj) of the stacked semiconductor chips 2. Thereafter, the substrate height Z0 in the vicinity of the chip is measured. For example, the Z-axis inspection machine 5 measures the height Zc by reading the focal length of the reflected light obtained by irradiating the measurement target (semiconductor chip) with laser light (step S2). For example, when the Zc measurement value is 0.582 mm, Zc−Zo = 0.582−0.064 = 0.518 mm, and the control unit 4 is close to Z4 = 0.50 mm from the Z-axis height data. From this, it is determined that the data is the height data up to the surface of the fourth-layer semiconductor chip 2 (step S3). Therefore, since the control unit 4 can determine that the semiconductor chip 2 is missing the 5th layer and the 6th layer, Vz5 + Vz6 = 0.00346 + 0.00274 = 0.00620 cc is added to the reference amount from the resin amount data and the resin is supplied. The amount is determined (step S4).

  The control unit 4 transmits control data related to the resin supply amount to the resin supply unit 6 for each work W on which the semiconductor chips 2 arranged in a matrix or a map are mounted (step S5). The resin supply unit 6 accumulates control data for one workpiece W (step S6), and supplies the liquid resin onto the substrate 1 for each chip or for each cavity (step S7). The control data accumulated for each work W is accumulated as a resin supply amount. Further, by performing feedback control as the resin supply amount for the workpiece W having the same missing content after the next time, the resin supplement amount can be analyzed and supplied without excess or deficiency. The above resin sealing operation is repeated. In this embodiment, the mold 81 provided with the collective sealing cavity 71 is filled with the liquid resin 6c in an amount corresponding to the semiconductor chip defect portion 21 in the work W to maintain the resin pressure and to seal the resin. The case of stopping (see FIG. 3C) has been described. However, when the workpiece W is resin-sealed in the mold 82 provided with the individual cavities 72, the cavities in which the chip is lost to eliminate waste of resin. It is also possible to instruct the resin supply unit 6 not to supply the liquid resin 6c into the 72 (see FIG. 3D).

  In the above embodiment, the Z-axis height measurement is performed using the Z-axis inspection machine 5, but the workpiece W may be imaged and the defect of the semiconductor chip may be detected by image processing. The Z-axis height position of the semiconductor chip 2 is measured from, for example, the focal length to the uppermost semiconductor chip 2 to be imaged or the shape of the semiconductor chip 2.

  As described above, when resin-sealing a workpiece W in which a plurality of semiconductor chips 2 are stacked, molding is performed by supplying an amount of resin corresponding to the chipped portion of the semiconductor chip and taking advantage of expensive non-defective products. Variations in product height can prevent molding defects and wasteful use of the sealing resin.

  As described above, various preferred embodiments of the present invention have been described. However, the sealing resin is not limited to a liquid resin, and may be a powdered or granular resin. It may be before or after being carried into the mold.

It is a block diagram which shows the structure of the control system of a resin sealing device. It is a flowchart of resin supply operation | movement. It is explanatory drawing which shows an example of a workpiece | work.

Explanation of symbols

W Work 1 Substrate 2 Semiconductor chip 3 Spacer 4 Control unit 5 Z-axis inspection machine 6 Resin supply unit 6b Dispenser nozzle 6c Liquid resin 21 Semiconductor chip missing part 71, 72 Cavity 81, 82 Mold

Claims (4)

In a resin sealing method in which a work in which a semiconductor chip is stacked on a substrate is carried into a mold and compression-molded,
Storing the volume of the semiconductor chip and the resin filling amount in correspondence with each other;
A step of measuring the Z-axis height from the substrate surface to the uppermost chip among the semiconductor chips stacked on the workpiece; and
Determining the chip stacking amount from the Z-axis height measurement value, and calculating a resin amount to be compensated for an insufficient semiconductor chip or a resin amount not to be compensated;
Instructing the resin supply unit as control data on the amount of resin to be compensated or the amount of resin not to be supplied;
A resin sealing method comprising: collecting control data for each workpiece and supplying a sealing resin from the resin supply unit to the workpiece.   The resin sealing method according to claim 1, wherein the resin compensation amount is calculated as a resin amount corresponding to a lacking volume of the semiconductor chip.   The resin sealing method according to claim 1, wherein the chip stacking height of the workpiece is measured using a Z-axis inspection machine.   The resin sealing method according to claim 1, wherein the chip stacking height of the workpiece is measured by an image taken by an imaging device.

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