JPH02260548A - Opening device for resin-sealed ic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [1 Already Required] Regarding the resin-sealed IC unsealing device that unseals the resin encapsulating the IC chip down to the chip, the structure of the resin-sealed IC under test and the solubility of the molding material in sulfuric acid are described. The purpose of the present invention is to provide a resin-sealed IC unsealing device that sets the mode corresponding to the above conditions and reliably unseals the resin-sealed IC under test. A first mode in which when the second galvanometric means galvanizes the first/second current, it starts counting for a preset time and unseals the resin-sealed IC down to the chip by the end of counting; a second galvanometer for controlling the stop of the sulfuric acid pump for injecting sulfuric acid through the jet nozzle when the second galvanometer galvanizes the second current after the galvanometer means galvanizes the first current; The mode is configured to include a control means that can set and select at least a mode.

[Industrial application field]

The present invention relates to a resin-sealed IC unsealing device for unsealing a resin enclosing an IC chip down to the chip.

Normally, when a resin-sealed IC becomes damaged, an unsealing device is used to unseal the plastic mold, which is the resin that encloses the IC chip, in order to investigate the cause.

[Conventional technology]

Fig. 5 is a diagram explaining the configuration outline of a resin-sealed IC, Fig. 6 is a diagram explaining a conventional example of a resin-sealed IC unsealing device, Fig. 7 is a diagram explaining the unsealing situation, and Fig. 8 is a control Figures illustrating flowcharts in a conventional example of the device are shown.

Figure 5 shows an outline of the configuration of the resin-sealed ICI to be tested.
The inside includes a pedestal plate 1a, a lead frame le, and a chip 1.
The base plate 1a has the chip 1c mounted thereon as described above, and the lead frame 1e is connected to each lead terminal 1b in correspondence with the chip 1c. Connect with wire ld,
This is for connecting the chip 1c to the outside via each lead terminal 1b.

FIG. 6 shows one of the conventional examples of a resin-sealed IC unsealing device,
It is equipped with a resin-sealed ICI for testing, sodium sulfate 2, a galvanometer 3, and a control device 4.

The above-mentioned test resin-sealed ICI includes a pedestal plate 1a for mounting a chip lc, a chip 1c and a lead frame le.
and a lead terminal 1b connected to the lead frame 1e for connecting the sample resin-sealed IC 1 to the outside. Sulfuric acid (
a) a sulfuric acid pump 22 applying pressure to inject;
There is a waste liquid tank (C) that collects the injected sulfuric acid (a), and a heating heater (rotor) installed on both sides of the sodium sulfuric acid 2 to maintain the temperature of the injected sulfuric acid (a) at about 200-odd degrees Celsius. ), and the control device 4 includes a timer circuit 41 that counts a preset time when the galvanometer 3 galvanizes the current.

The resin-sealed IC unsealing device configured as described above melts the plastic mold, which is the resin that encloses the chip IC, by spraying sulfuric acid (a) at about 200 °C to the chip LC. It must be opened.

FIG. 7 shows the order of unsealing a resin-sealed ICI, in which the jet nozzle 21 sprays sulfuric acid (a) in the direction of the upward arrow in the figure, and the spray reaches the position where the chip IC is sealed. The dotted line ■ indicates that galvanometer 3 is showing current! The dotted line ■ indicates the position from when the timer is started to when it is stopped.

Further, FIG. 8 shows a flowchart in a conventional example of the control device R4 that controls the opening procedure, and shows the control procedure from the start of the sulfuric acid pump 22 until the timer ends and the operation of the sulfuric acid pump 22 is stopped.

The opening operation of the conventional example will be explained below based on FIGS. 5 to 8.

That is, in order to spray sulfuric acid (a) onto the resin-sealed ICI, a certain pressure is applied by the sulfuric acid pump 22 to the jet nozzle 21.
The temperature of the sulfuric acid (a) is about 200-odd degrees Celsius to make it easier to melt the plastic mold.

Moreover, the direction of the arrow in the sodium sulfuric acid 2 shown in FIGS. 6 and 7 indicates the direction and position of the jet from the jet nozzle 21, and the direction of returning the jetted sulfuric acid (a) to the waste liquid tank (C). show.

The plastic mold is melted by spraying sulfuric acid (a), and the wire l connecting the lead frame 1e and the chip IC is
When sulfuric acid (a) reaches d, sulfuric acid (a) and lead terminal tb
A current 11 flows due to the voltage (5V to 10V) of the power supply V applied between the two.

The galvanometer 3 galvanizes the flow of this current IS and sends a galvanometric signal to the timer circuit 41 in the control device 4.

The timer circuit 41 starts counting a preset time based on this galvanometric signal.

When the timer circuit 41 finishes counting the pre-calibrated time (for example, when the pre-set value is subtracted and reaches zero), it outputs a control signal to stop the sulfuric acid pump 22, and the sulfuric acid pump 22 is stopped. The operation of the pump 22 is stopped, and sulfuric acid (a
) stops spraying.

That is, the plastic mold is melted to the position indicated by the dotted line ■ in Fig. 7 (and the wire ld is exposed to sulfuric acid (a),
A loop is formed between the lead terminal 1b and the sulfuric acid (a), and a current of 1. flows.

When the plastic mold melts to the dotted line ■, the chip 1c has not been completely opened yet, and there remains between the dotted lines ■ and dotted lines ■, so add sulfuric acid (a) from the dotted line ■ to the dotted line ■. It needs to be sprayed.

The time set in the timer circuit 41 is the injection time of sulfuric acid (grape) from the dotted line ■ to the dotted line ■.
This time is set to be approximately constant, and it is assumed that the opening of chips up to the chip 1c will be completed by this time.

Note that the time set in the timer circuit 41 is set based on past results.

[Problem to be solved by the invention]

However, in the conventional example described above, when the chip LC is completely unsealed, the time taken to melt by spraying sulfuric acid (a) depends on the sealing shape and the material of the plastic mold. In some cases, the chip IC may not be completely opened during this time.

Further, in some cases, the package may be opened beyond the chip IC and beyond the pedestal plate la.

Therefore, a plurality of test resin-sealed ICs 1 are required, which takes time, and a plurality of test resin-sealed ICs 1 are required.
If the details of each failure are different, it may be difficult to conduct all failure investigations reliably.

The present invention provides a resin-sealed IC unsealing device that sets a mode corresponding to the structure of the resin-sealed IG under test, the solubility of the molding material in sulfuric acid, etc., and reliably unseals the resin-sealed IC under test. The purpose is to

(Means for Solving the Problems) FIG. 1 shows a diagram illustrating the principle of the resin-sealed IC opening device of the present invention.

The resin-sealed IC unsealing device of the present invention shown in FIG. Flow means 3a, second
The test resin-sealed ICI and the sodium sulfuric acid 2 are as shown in FIGS. 4 and 5.
The first galvanometric means 3a has the same content as explained in the figure, and the first galvanometric means 3a is a sulfuric acid (sulfuric acid) sprayed onto the wire connecting the lead frame of the resin-sealed IC 1 and the chip. is connected to the resin-sealed I
The lead terminal 1b that connects the CI to the outside is the negative electrode, and the sodium sulfate 2
A first current flowing through a first circuit formed by connecting a power source V with the internal sulfuric acid (a) as a positive electrode.1. The second galvanometric means 3b uses sulfuric acid (sulfuric acid by injection of grapes).

When the acid (a) reaches the pedestal base plate or lead frame inside the resin-sealed ICI, a power source V is connected with the pedestal plate 1a or the lead frame as the negative electrode and the sulfuric acid (a) inside the sulfuric acid port 2 as the positive electrode. The second current I8 flowing through the second circuit is galvanized, and the control means 4a is the first/second galvanization means 3a.

When 3b galvanizes the first/second currents t,, It, it starts counting for a preset time, and a first mode in which the resin-sealed ICI is opened by the end of counting, and a first mode in which the resin-sealed ICI is opened; After the current means 3a galvanizes the first current ■1, the second current means 3
At least a second mode for controlling the stop of the sulfuric acid pump 22 for injecting the sulfuric acid (a) through the ejection nozzle 21 when the second current Ig is detected by the second current Ig can be set and selected; This is a means to solve this problem by providing the following.

[For production]

In the first mode for unsealing the resin-sealed ICI to the chip, if the pedestal plate 1a and the chip are not insulated, the control means 4a counts a preset time and unseals the chip. The structure of the resin-sealed ICI allows mode setting within the control means 4a.

On the other hand, in the second mode, in the case of a resin-sealed ICI under test in which the pedestal plate 1a on which the resin-sealed ICI chip is mounted is electrically insulated from the chip and the lead frame, the pedestal plate 1a is connected to an independent electrode. Used as sulfuric acid (a) and pedestal plate 1
8, a second current I! is applied when the sulfuric acid (a) reaches the base plate 1a. is galvanized by the galvanometric means 3a, and the control means 4a sends this galvanometric signal to the sulfuric acid pump 22 as a signal to stop the sulfuric acid pump 22.
stop the operation.

In this case, the pedestal plate 1a is located at the same level as the chip, so when the sulfuric acid (a) reaches the pedestal plate 1a, it means that the chip has been opened, and the operation of the sulfuric acid pump 22 is stopped. By configuring the present invention, it is possible to provide a resin-sealed IC unsealing device that can reliably open one resin-sealed ICI under test.

〔Example〕

The gist of the present invention will be specifically explained below with reference to embodiments shown in FIGS. 2 to 4.

2 is a diagram illustrating an embodiment of the resin-sealed IC unsealing device of the present invention, FIG. 3 is a diagram illustrating a flowchart of the control device of the present invention, and FIG. 4 is a diagram illustrating an embodiment of the resin-sealed IC unsealing device of the present invention. Figures illustrating other embodiments are shown, respectively. Note that the same reference numerals indicate the same objects throughout the figures.

The resin-sealed IC unsealing device of the present invention shown in FIG. 2 is an example in which the pedestal plate 1a is used as an independent terminal, and the first/second galvanometric means 3a explained in FIG.

In this embodiment, galvanometers 31 and 32 are used as 3b, and a control device 4b is used as the control means 4a.

The above-mentioned galvanometer 31 galvanizes and detects the current I flowing in the circuit l formed between the sulfuric acid (a) in the sulfuric acid port 2 via the lead terminal 1b when the sulfuric acid (a) reaches the wire 1d. The flow meter 32 is a circuit 2 formed between the sulfuric acid (a) in the sulfuric acid port 2 and the pedestal plate 1a when the sulfuric acid (a) reaches the pedestal plate 1a.
The current flowing through ■2 is galvanized.

The control device 4 includes a timer circuit 41 that counts a preset time based on the galvanometric signal when the current It is galvanized, and a timer circuit 41 that stops the operation of the sulfuric acid pump 22 based on the galvanic signal when the current 2 is galvanized. A pump control circuit 42 that outputs a control signal to
and a mode setting circuit 43 for setting an opening mode from the outside.

FIG. 3 shows a flowchart for controlling the unsealing operation of the resin-sealed IC unsealing device of the present invention in the above-mentioned control device 4b. First, a mode is set based on the molding material and assembly shape of the resin-sealed ICI under test. However, as the unsealing progresses, the currents in circuits 1 and 2 are galvanized using galvanometers 31 and 32, and the procedure is shown until the operation of the sulfuric acid pump 22 is stopped.

Note that the following three types of opening modes can be set. That is, Mode 1: This is a mode set when the pedestal plate 1a is not insulated from the ground and one of the lead frames 1e corresponding to each lead terminal 1b (i.e., the ground terminal). The galvanometer 31 galvanizes the current (2) that flows when the wire a) touches the wire 1d, and the galvanometer signal activates the timer circuit 41 in the control device 4, and the unsealing is continued until the set time.

At this time, the mode setting circuit 43 outputs a control signal to stop the operation of the sulfuric acid pump 22 based on the completion signal when the pump control circuit 42 finishes counting by the timer circuit 41. Also, the direction of the jet nozzle 21 at this time is the tip lc.
It is assumed that it is directed to approximately the center position of .

Mode 2: This mode is set when the pedestal plate 1a is insulated from the ground terminal of the lead frame 1e, and when the pedestal plate 1a and the chip lc are not necessarily on the same level, and the sulfuric acid (a) is The galvanometer 32 galvanizes the current I8 that flows when the
1 and continue opening by the set time.

At this time, the mode setting circuit 43 is set to output a control signal to stop the operation of the sulfuric acid pump 22 based on a completion signal when the pump control circuit 42 finishes counting by the timer circuit 41.

Mode 3: This mode is set when the pedestal plate 1a is insulated from the ground terminal of the lead frame le, and when the pedestal plate 1a and the chip lc are at the same level, and sulfuric acid (a) is applied to the pedestal plate 1a. contact 42 to sulfuric acid pump 22
The control timer circuit 41, which stops the operation of the controller, is set not to be used.

The above three types of modes 1 to 3 are based on the structure of the resin-sealed ICI,
By using different molding materials to accommodate variations in solubility in sulfuric acid (a), etc., it becomes possible to reliably open one resin-sealed ICI under test.

FIG. 4 shows another resin-sealed IC unsealing device of the present invention, and the resin-sealed IC unsealing device of this embodiment is used as the first/second galvanometric means 3a and 3b explained in FIG. Flow meter 33. ．． 3
4. This is an embodiment in which a control device 4c is used as the control means 4a, and a test resin-sealed ICI and a dummy resin-sealed IC can be installed as resin-sealed ICs.
and a jet nozzle 21a corresponding to the dummy resin-sealed ICI'.
, 21b, and sulfuric acid pumps 22a and 22b are installed correspondingly, and similarly two power supplies VERr V
F6 is provided.

In addition, the resin-sealed ici for the test is the lead terminal ib and the sodium sulfate 2
A circuit 1 is formed between the sulfuric acid (a) inside the lead terminal 1b' and the sulfuric acid (a) inside the sulfuric acid 2'.
A circuit 2 is formed with a).

In addition, the power supply Vtt is connected to the lead terminal 1b and the sulfuric acid in the sulfuric acid 2' (
a), forming a circuit l corresponding to the first circuit explained in FIG. 1, and a power supply ■. is lead terminal tb'
and the sulfuric acid (a) in the sodium sulfate 2', forming a circuit 2 corresponding to the second circuit explained in FIG.

Furthermore, the galvanometer 33 detects the current flowing through the above-mentioned circuit l! The galvanometer 34 galvanizes the current 1 flowing through the circuit 2.
It is used to galvanometrically measure g.

The control device 4c of the present embodiment includes a first timer circuit 44 activated by the galvanometric signal from the galvanometer 33, and a second timer circuit 45 activated by the galvanic signal from the galvanometer 34. , 1st
/ A pump control circuit 46 that outputs a control signal to stop the operation of the sulfuric acid pumps 22a and 22b in response to a signal from the second timer circuit 44-45, and the first/second timer circuit 44-45 and the pump control circuit. 46 to correspond to a set mode.

Note that the flowchart by the control device 4c of this embodiment is as follows:
The procedure is approximately the same as that shown in FIG.

However, the mode is a mode for this embodiment, which will be explained below.

That is, the direction of the ejection nozzle 21b with respect to the dummy resin-sealed ICI' of this example is set to the position of the lead frame 1e, and the direction of the ejection nozzle 21a with respect to the resin-sealed ICI under test is set to a position near the center of the chip lc. .

In addition, the negative electrode of both the power supply V Current! flows, the galvanometer 33 galvanizes this current (1), and the first timer circuit 44 is activated by the galvanometer.

The mode when one is used as a dummy resin-sealed ICI' is that when sulfuric acid (a) reaches the lead frame le, a current I3 flows through the circuit 2, and the galvanometer 34 galvanizes this current. The second timer circuit 45 is activated.

When the chip IC is completely unsealed by the time the second timer circuit 45 ends, a current I flows, which is galvanized by the galvanometer 33, and this galvanic signal causes the pump control circuit 4
6 stops the operation of the sulfuric acid pump 22a.

At this time, the mode setting circuit 47 sets the first timer circuit 44 not to start, and also sets the second timer circuit 44 so that the first timer circuit 44 does not start.
5, the pump control circuit 46 simultaneously sends a signal to stop the operation of the sulfuric acid pump 22b.

In addition, the dummy resin-sealed ICI' was replaced with the second test resin-sealed ICI'.
In the mode C, in which the ejection nozzle 21b is oriented near the center of the chip, two test resin-sealed ICs can be opened at the same time.

At this time, the mode setting circuit 47 operates the first and second timer circuits 44 and 45 independently, and the pump control circuit 46 also operates each of the first and second timer circuits 44 and 45 independently. The setting is such that the operation of the corresponding sulfuric acid pumps 22a and 22b is stopped.

As described above, it is possible to reliably unseal the chip by setting the unsealing method according to the mode in consideration of the structure of the test resin-sealed IC, the solubility of the molding material in sulfuric acid, etc.

〔Effect of the invention〕

According to the present invention as described above, it is possible to provide a resin-sealed IC unsealing device that selects an optimal unsealing method for the resin-sealed IC under test and can reliably unseal each resin-sealed TC under test. I can do it.

[Brief explanation of drawings]

Fig. 1 is a diagram explaining the principle of the resin-sealed IC unsealing device of the present invention, Fig. 2 is a diagram illustrating an embodiment of the resin-sealed ICC unsealing electrical device of the present invention, and Fig. 3 is a diagram explaining the control device of the present invention. 4 is a diagram illustrating another embodiment of the resin-sealed IC unsealing device of the present invention. FIG. 5 is a diagram illustrating an outline of the configuration of the resin-sealed IC. FIG. 7 is a diagram illustrating a conventional example of a resin-sealed IC opening device, FIG. 7 is a diagram illustrating an unsealing situation, and FIG. 8 is a diagram illustrating a flowchart of a conventional example of a control device. In the figure, 1 is a test resin-sealed IC 1, 1' is a dummy resin-sealed IC 1, 1a is a pedestal plate, lb, lb' are lead terminals, 1c is a chip, 1d is a wire, 1e is a lead frame, 2 is sodium sulfate, 3.31 to 34 are galvanometers, 3a is a first galvanometer, 3b is a second galvanometer, 4.4b and 4c are control devices, 4a is a control means, 21, 21 a, 2 l b is a jet nozzle, 22
．． 22a and 22b are sulfuric acid pumps, 41 is a timer circuit, 42.46 is a pump control circuit, 43.47 is a mode setting circuit, 44 is a first timer circuit, and 45 is a second timer circuit. Tsu Z diagram rate 4 diagram N1 1 1 peeking situation and explanation B8 diagram mourning 7 closing]] 23-]]]] - + day and day to explain mart

Claims (1)

[Claims] The sulfuric acid ((a)) retained in the sodium sulfate (2) is used to remove the resin that encapsulates the chip of an IC (integrated circuit).
21) is an unsealing device for a resin-sealed IC that unseals the chip by spraying water through the resin-sealed IC (1), the resin-sealed IC (1) being connected to the chip via a wire, and each lead terminal (1b) When the injected sulfuric acid ((a)) reaches the wire connecting the lead frame and the chip, which are connected in accordance with 1b)
The first current (I_1) flows through the first circuit formed by connecting the power supply (V_E) with the side where all of the sulfuric acid is connected as the negative electrode and the sulfuric acid ((a)) in the sodium sulfate (2) as the positive electrode. By spraying the sulfuric acid ((a)) galvanizing the sulfuric acid ((a)
)) reaches the pedestal plate (1a) or the lead frame on which the chip in the resin-sealed IC (1) is mounted, the pedestal plate (1a) or the lead frame is connected to the negative electrode and the sodium sulfate (2) Power supply (V_E) using sulfuric acid ((a)) as the positive electrode
) is connected to form a second circuit formed by a second current (
a second galvanometric means (3b) for galvanizing the current I_2), and the first/second galvanizing means (3a, 3b) galvanizing the first/second galvanizing means
A first mode in which counting is started for a preset time when the second current (I_1, I_2) is galvanized, and the resin-sealed IC (1) is unsealed down to the chip by the end of counting; The first current (I_1)
), and when the second galvanometric means (3b) galvanizes the second current (I_2), the sulfuric acid ((a)) is injected through the jet nozzle (21). 1. A resin-sealed IC unsealing device comprising: a second mode for controlling stoppage of a sulfuric acid pump (22); and a control means (4a) for setting and selecting at least a second mode.