JPH0226048Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a leak test device used to detect the amount of leakage from a test object such as an IC package.

(B) Prior art This type of leak test device includes a sealable chamber that houses a test object filled with probe gas (leak gas), and a starting end connected to this chamber, and is configured to exhaust the inside of the chamber. an exhaust system, a vacuum pump that is interposed at the terminal end of the exhaust system and sucks gas in the chamber through the exhaust system, and an analyzer that detects probe gas exhausted through the exhaust system. There are some that are equipped with the following. In such a case, open the chamber lid and place the test object in the chamber,
The lid is closed to seal the inside of the chamber, and the vacuum pump is driven to exhaust gas from the exhaust system. At this time, if the probe gas leaks from the test object, the probe gas will also be exhausted from the exhaust system, so the analyzer will detect this and know that there is a defect in the test object. I'm starting to get it.

However, such a leak test device has the following problems. That is, dust (ceramic powder, peeled plating, etc.) is generated in the chamber from the test object,
The problem is that such dust adheres to the seal portion of the chamber, causing gas leakage from the seal portion. In order to solve such problems, conventionally,
Wiping the seal portion etc. with gauze etc. is practiced. However, such a device has the disadvantage that it is difficult to sufficiently clean the recessed portion of the seal portion, and dust can only be removed insufficiently. Conventionally, the inside of the chamber has also been cleaned using a vacuum cleaner, and in this way, dust can be reliably removed. However, having a vacuum cleaner specially installed has the disadvantage of increasing the number of components and increasing costs.

(c) Purpose The inventor of this invention focused on this situation and the fact that a vacuum pump for exhaust is not used when cleaning the chamber, and decided to use the vacuum pump used for exhausting the chamber to clean the inside of the chamber. If possible, there would be no need for a separate pump for cleaning.
The present invention was created based on the idea that it would be possible to reduce the number of components and reduce the cost. In other words, the present invention can sufficiently remove dust from inside the chamber, and
To provide a leak test device that does not require a special pump, can reduce the number of components, and can reduce costs.

(d) Structure In order to achieve the above object, the present invention provides a cleaning system in the conventional leak test device, which branches from one of the exhaust system paths and has a suction port at the tip for sucking the dust in the chamber. The present invention is characterized by providing a path and a path switching means for selectively opening one of the exhaust system paths and the cleaning path.

(E) Embodiment An embodiment of the present invention will be described below with reference to the drawings.

A chamber 1 for sealing an IC package A, which is a test object filled with a probe gas, is provided, and a lid 2 is attached to the upper end 1a of the chamber 1 so as to be openable and closable. The lid 2 and the chamber 1 are sealed at a sealing portion 3.
Furthermore, the starting ends of an initial exhaust system path 4 and a main exhaust system path 5 are connected to the bottom portion 1b of this chamber 1.
The initial exhaust system line 4 includes an initial exhaust pipe line 6 whose starting end is opened into the chamber 1, and this initial exhaust line 6.
It has a filter 7 and a solenoid valve 8 inserted therein. An oil rotary vacuum pump 9 for exhaust is interposed at the terminal end of this initial exhaust pipe line 6.
The main exhaust line 5 also includes a main exhaust line 11 that shares a tip with the initial exhaust line 6, and a filter that is inserted into the main exhaust line 11 and that is common to the initial exhaust line 4. 7, a solenoid valve 12, a cold trap 13, a diffusion pump 14, and a solenoid valve 15. An oil rotary vacuum pump 16 is interposed at the terminal end of this main exhaust system path 5. The cold trap 13 also has a mass spectrometer 1 which is a gas detection means for detecting the probe gas.
7 is connected.

In such a leak test device, a cleaning line 18 and a line switching means 19 are provided. The cleaning line 18 is formed by branching from a portion of the initial exhaust system line 4 on the previous stage side than the oil rotary vacuum pump 9, and has a suction port 21 at its tip and a base end connected to the initial exhaust line 4. A cleaning conduit 22 connected to the cleaning conduit 22, a filter 23 inserted in this cleaning conduit 22, and a solenoid valve 2.
4. And the cleaning pipe 22
The distal end portion of the chamber has a structure that can be flexibly deformed so that the suction port 21 can freely extend to the lid 2 portion of the chamber. In addition, the system switching means 1
9 comprises a solenoid valve 8 for the initial exhaust system path 4, a solenoid valve 24 for the cleaning system 18, and a switching circuit 25 for selectively opening these solenoid valves 8, 24. It is something.

Next, the operation of this device will be explained.

Open the lid 2 of the chamber 1, place the IC package A into the chamber 1, close the lid 2, and place the IC package A into the chamber 1.
Package A is sealed within the chamber 1. Next, the solenoid valve 8 of the initial exhaust system path 4 is opened, and the oil rotary vacuum pump 9 is driven to drive the chamber 1.
The gas inside is sucked by the pump 9 and exhausted from the initial exhaust pipe line 6 of the initial exhaust system line 4. and,
When the inside of the chamber 1 becomes a certain degree of vacuum, the solenoid valve 8 is closed and the oil rotary vacuum pump 9 is stopped, while the solenoid valves 12 and 15 of the main exhaust system path 5 are opened and the diffusion pump 14 is stopped. and drives the oil rotary vacuum pump 16. By this operation, the gas in the chamber 1 is sucked by the diffusion pump 14 and the oil rotary vacuum pump 16 and exhausted from the main exhaust pipe 11, resulting in a higher vacuum. At this time, if the probe gas such as He sealed in the IC package A leaks from the IC package A, the probe gas is also exhausted from the main exhaust pipe line 11 of the main exhaust system line 5. The probe gas thus exhausted is detected by a mass spectrometer 17 provided in the cold trap 13.

When the leak test is completed in this manner, the solenoid valves 12 and 15 are closed, and the diffusion pump 14 and oil rotary vacuum pump 16 are stopped. Then, open the lid 2 and insert the IC from inside the chamber 1.
Take out package A. Thereafter, the seal portion 3, bottom portion 1b, etc. of the chamber 1 are cleaned by the cleaning path 18. That is, by switching the switching circuit 25 of the system switching means 19, the solenoid valve 8 of the initial exhaust system 4 is closed, and the cleaning system 1 is closed.
8 is opened, the suction port 21 is brought close to the seal portion 3 and the bottom portion 1b, and the oil rotary vacuum pump 9 is driven. Through this operation, the oil rotary vacuum pump 9 suctions the dust present in the seal portion 3 and the bottom portion 1c, and drains the cleaning conduit 2 from the suction port 21.
2 to clean the seal portion 3 and bottom portion 1b. The dust thus sucked in adheres to the filter 23, and only gas flows into the oil rotary vacuum pump 9.

After cleaning chamber 1 in this way,
The suction port 21 is separated from the chamber 1, another IC package A as a test object is housed in the chamber 1, and the lid 2 is closed to seal the inside of the chamber 1. Subsequently, the system switching means 19 closes the electromagnetic valve 24 and opens the electromagnetic valve 8. Through this operation, the gas in the chamber 1 is exhausted through the initial exhaust system path 4. Thereafter, a leak test for IC package A is performed using the same procedure as described above.

In this way, the leak test is carried out. According to this embodiment, the bottom 1 of the chamber 1
b and the seal portion 3 are cleaned by the cleaning line 18 branched from the initial exhaust line 4, so the oil rotary vacuum pump used for exhaust can be used as is for cleaning. Compared to cleaning using a conventional electric vacuum cleaner, there is no need to provide a special pump, and the number of components can be reduced and costs can be reduced. Furthermore, since the initial exhaust system 4 is not used when cleaning the chamber 1, and the cleaning system 18 is not used during the initial exhaust, problems such as a decrease in suction force caused by using both systems at the same time do not occur. Therefore, a single conventional oil rotary vacuum pump can perform both the exhaust and cleaning functions, and there is no need to provide a pump with a larger capacity.

It should be noted that the present invention is of course not limited to the above-mentioned embodiments, and the exhaust system into which the cleaning system is branched is not limited to the initial exhaust system, but may be the main exhaust system. Furthermore, in the case of a leak test device having many exhaust system paths, the cleaning system may be branched from any of the exhaust system paths.

Furthermore, the test object is not limited to an IC package.

Further, the system switching means may be of any type as long as it can selectively open the cleaning system and the exhaust system.

Various other modifications can be made without departing from the spirit of the present invention.

(f) Effects Since the present invention has the above-described configuration, it is possible to sufficiently remove dust from inside the chamber.
Furthermore, it is possible to provide a leak test device that does not require a special pump and can reduce the number of components and reduce costs.

[Brief explanation of the drawing]

The drawing is an explanatory diagram of a system showing an embodiment of the present invention. 1...Chamber, 4...Initial exhaust system path, 5...
Main exhaust system path, 18... Cleaning system path, 19... System switching means, A... Test object (IC package).

Claims (1)

[Scope of utility model registration request] The test object comprises a sealable chamber for accommodating a test object, an exhaust system for evacuating the inside of the chamber, and a gas detection means connected to the exhaust system for detecting probe gas leaking from the test object. In a leak test device configured to perform a leak test on a test specimen, a cleaning line is provided that branches from the exhaust system line and has a suction port at its tip for sucking in the dust in the chamber, and the exhaust line is connected to the exhaust line. A leak test device comprising a system switching means for selectively opening a cleaning system and a cleaning system.