Test handler and operation method thereof

A test handler is disclosed. A posture changing unit for changing a posture of a test tray on which semiconductor devices have been loaded changes the posture of the test tray in a soak chamber. While the posture of the test tray is changed, the devices can be pre-heated/pre-cooled, thereby reducing the soak chamber length and the pre-heating/pre-cooling time.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 10-2005-0124223, filed Dec. 15, 2005, in the Korean Intellectual Property Office, the entire disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a test handler for supporting a test of semiconductor devices. More particularly, the present invention relates to an arrangement structure and an operation method of a posture changing unit of the test handler for changing the posture of a test tray.

2. Description of the Related Art

In general, a test handler supports a test of semiconductor devices (hereinafter, referred to as a ‘device’) manufactured through a predetermined manufacturing process, and sorts and loads the devices on user trays according to the test results. To sort the devices according to the test results, the test handler circulates a test tray against a tester head. The test handler is classified into an under head docking type and a side docking type according to a docking method between the test handler and a tester.

The side docking type test handler transfers devices from user trays to a horizontal posture test tray, changes the horizontal posture of the device-loaded test tray into the vertical posture, pre-heats/pre-cools the vertical posture test tray, and connects the vertical posture test tray to a vertical posture tester head. After the test, the test handler restores the vertical posture test tray to the normal temperature, changes the vertical posture of the test tray to the horizontal posture, and sorts and unloads the devices to the user tray according to the test results.

As publicly known, the side docking type test handler includes a loading unit, a vertical posture changing unit, a soak chamber, a test chamber, a de-soak chamber, a horizontal posture changing unit and an unloading unit. The structure of the test handler will now be briefly explained with reference toFIG. 12.

The loading unit1120transfers and loads devices loaded on user trays1110to a horizontal posture test tray.

The vertical posture changing unit1130is positioned in the upward direction of the soak chamber1200, and changes the horizontal posture of the test tray into the vertical posture before supplying the test tray to the soak chamber1200.

The soak chamber1200sequentially receives the test trays posture-changed into the vertical posture by the vertical posture changing unit1130, and has a temperature environment for pre-heating/pre-cooling the devices loaded on each test tray. The test trays entering the soak chamber1200are translated closely to the test chamber1100with the vertical posture. During the translation, the devices loaded on the test trays are sufficiently pre-heated/pre-cooled.

The test chamber1100is installed to the test handler, in which the devices loaded on the test tray supplied from the soak chamber1200can be tested by a tester. For this, the test chamber1100has a temperature environment for testing the devices.

The de-soak chamber1300(restoring chamber) restores the heated or cooled devices to the normal temperature.

The horizontal posture changing unit1230is positioned in the upward direction of the de-soak chamber1300for changing the vertical posture of the test tray transferred from the de-soak chamber1300to the horizontal posture.

The unloading unit1260sorts and unloads (transfers and loads) the test-completed devices to user trays1310according to the test results.

With the recent increase in demand and production of devices, the test handler has been developed to increase the number of devices tested at a time by loading many devices on one test tray, namely, to enlarge the test tray to carry many devices. If the test tray is two-dimensionally enlarged to test many devices at a time, the space for changing the posture of the test tray is three-dimensionally enlarged.

In the side docking type test handler, the posture changing unit is installed in the upward direction of the soak chamber, and the test tray posture-changed by the posture changing unit is transferred in the downward direction and received in the soak chamber. When the side. docking type test handler adopts the enlarged test tray, the whole size of the test handler must be increased more than the enlarged size of the test tray by a few times in order to prevent interferences between the space for changing the posture of the test tray and the wall of the soak chamber. However, the test handler can be put into practical use only under a predetermined external appearance standard (such as width, length and height). As a result, in relation to the enlargement tendency of the test tray, the test handler has already reached the maximum size.

Furthermore, since the pre-heating/pre-cooling process is started after the vertical posture change of the test tray, the soak chamber must have a relatively long translation section. It is thus difficult to reduce the length of the test handler and the pre-heating/pre-cooling time.

SUMMARY OF THE INVENTION

Therefore, the present invention has been made in view of the above problems and/or disadvantages, and it is an object of the present invention to provide a technique of increasing the size of a test tray without seriously increasing the overall size of a test handler.

It is another object of the present invention to provide a technique of obtaining a posture changing time and a pre-heating/pre-cooling time of a test tray, while reducing the overall processing time of a test handler.

In accordance with the present invention, the above and other objects can be accomplished by the provision of a test handler, including: a loading unit for loading devices loaded on user trays onto a test tray; a posture changing unit for changing a posture of the test tray on which the devices have been loaded by the loading unit; a soak chamber for sequentially receiving the test trays posture-changed by the posture changing unit; a test chamber in which the devices loaded on the test tray supplied from the soak chamber are tested by a tester; a temperature controller for pre-heating/pre-cooling the devices loaded on the test tray before supplying the test tray to the test chamber; and an unloading unit for unloading the devices test-completed in the test chamber onto the user trays. Here, the temperature controller continuously pre-heats/pre-cools the devices on the test tray while the test tray is posture-changed by the posture changing unit and received in the soak chamber. Also, the posture changing unit includes a rotator posture-changeably installed in the soak chamber for holding the test tray entering the soak chamber and a first power source for providing power for changing the posture of the rotator.

In exemplary implementation of the present invention, the first power source is installed outside the soak chamber and separated from pre-heating/pre-cooling of the temperature controller.

In exemplary implementation of the present invention, the test handler further includes a stopper unit for preventing separation of the test tray during the posture change of the rotator.

In exemplary implementation of the present invention, the stopper unit includes: a stopper for hooking or unhooking the rear end of the test tray which has entered the rotator; a second power source for providing power for the operation of the stopper; and a power transmitting shaft for transmitting power from the second power source to the stopper.

In exemplary implementation of the present invention, the second power source is installed outside the soak chamber and separated from pre-heating/pre-cooling of the temperature controller.

In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of an operation method of a test handler, including: a loading step of loading devices of user trays onto a test tray; a posture changing step of changing a posture of the test tray with pre-heating/pre-cooling the devices on the test tray after completing the loading step; a translation step of translating the test tray posture-changed in the posture changing step with continuously pre-heating/pre-cooling the devices on the test tray; a test step of testing the devices pre-heated/pre-cooled in the posture changing step and the translation step; and an unloading step for unloading the devices test-completed in the test step from the test tray to the user trays.

In exemplary implementation of the present invention, the loading step loads the devices of the user trays onto the horizontal posture test tray, and the posture changing step changes the horizontal posture of the test tray into the vertical posture.

In exemplary implementation of the present invention, the translation step sequentially receives and translates the posture-changed test trays with pre-heating/pre-cooling the devices on each test tray.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In accordance with an exemplary embodiment of the present invention, a test handler includes a loading unit, a soak posture changing unit (vertical posture changing unit), a soak chamber, a test chamber, a de-soak chamber, a de-soak posture changing unit (horizontal posture changing unit), and an unloading unit. The technical contents of the loading unit, the test chamber, the de-soak chamber and the unloading unit which are not closely associated with an exemplary embodiment of the present invention have been publicly known and briefly mentioned in the background art. Therefore, detailed explanations thereof are omitted for clarity and conciseness.

According to the technical characteristic of an exemplary embodiment of the present invention, the vertical posture changing unit is installed in the soak chamber, in more detail, a rotator of the posture changing unit is installed in the soak chamber, so that a test tray can be pre-heated/pre-cooled during the vertical posture change. This structural characteristic will now be explained in detail with reference toFIGS. 1 to 8.

FIG. 1is a schematic side view illustrating an inside structure of a soak chamber in the test handler according to an exemplary embodiment of the present invention.FIG. 2is a perspective view illustrating a posture changing unit according to an exemplary embodiment of the present invention.FIG. 3is a cross-sectional view taken along line V-V ofFIG. 2.FIG. 4is a side view seen from III-III direction ofFIG. 2according to an exemplary embodiment of the present invention.FIG. 5is a schematic bottom view illustrating a stopper and a second power transmitting shaft arranged in the posture changing unit ofFIG. 2according to an exemplary embodiment of the present invention.

Referring toFIG. 1, the test handler1includes a soak chamber10, a soak posture changing unit100, a test chamber13, a first temperature control unit150and a second temperature control unit180. The soak posture changing unit100performs vertical posture change of a test tray20in the soak chamber10. The soak chamber10and the test chamber13are linked to each other, for example, in an L shape on the plan view. A de-soak chamber (not shown) is disposed at the side of the test chamber13symmetrically to the soak chamber10. A de-soak posture changing unit (not shown) is positioned on the de-soak chamber. For example, the de-soak posture changing unit can have the same structure as that of the soak posture changing unit100. The soak chamber10, the test chamber13and the de-soak chamber can be arranged, for example, in a U shape on the plan view.

In the soak chamber10, the vertical posture change and translation of the test tray20are sequentially carried out with continuously pre-heating/pre-cooling the test tray20. During the vertical posture change, the test tray20is pre-heated/pre-cooled mainly by the first temperature control unit150positioned at the upper portion of the test chamber13, and during the translation, the test tray20is pre-heated/pre-cooled mainly by the second temperature control unit180positioned at the lower portion of the soak chamber10. In addition, the first temperature control unit150selectively supplies hot or cold air to a test chamber region (standby unit in which the test tray20finishing the translation and the pre-heating/pre-cooling stands by to enter a test unit) at the rear portion of the soak chamber10. At least any one of the first temperature control unit150and the second temperature control unit180can include a heater for emitting heat, a heater fan for diffusing the heat emitted from the heater to the test tray side, and a nozzle for injecting LN2 gas.

The soak posture changing unit (or vertical posture changing unit)100changes a horizontal posture of the test tray20into a vertical posture in the soak chamber10. The soak posture changing unit100includes a rotator110, a first power source, a first power transmitting shaft112R, a stopper120, a second power source, a second power transmitting shaft122, a flange130and a bearing140. On the other hand, the de-soak posture changing unit (not shown) changes a vertical posture of the test tray20into a horizontal posture inside or outside the de-soak chamber (not shown). The de-soak posture changing unit can have the same structure as that of the soak posture changing unit100, which is not intended to be limiting. Hereinafter, the posture changing unit means the soak posture changing unit100. Preferably, the de-soak posture changing unit performs horizontal posture change of the test tray20in the de-soak chamber. This structure enables the semiconductor devices to be heated or cooled during the horizontal posture change of the test tray20, so that the semiconductor devices can be stably restored to the normal temperature. In this case, the inside temperature of the de-soak chamber relatively approximates to the normal temperature. Accordingly, even if the entire components of the de-soak posture changing unit are installed in the de-soak chamber, durability of the de-soak posture changing unit is not reduced. Differently from the de-soak posture changing unit, the soak posture changing unit100must be operated at a considerably high or low temperature. Therefore, the soak posture changing unit100needs a structure for preventing reduction of durability, which will be described later.

The rotator110is positioned at the upper portion of the inside space of the soak chamber10. The rotator110is axially coupled to one side wall of the soak chamber10through a rotatable first power transmitting shaft112R, and axially coupled to the other side wall of the soak chamber10through an idling shaft112L. The rotator110is rotatable and holds the test tray20on which the test objects, namely, the devices have been loaded. A support stand110-2for supporting the test tray20entering along a pair of entering rails110-1R and110-1L is installed at the rear portion of the rotator110. A top cover110-3for covering the rotator110to cross the rotator110and connecting the center portions of the pair of entering rails110-1R and110-1L is bolt-coupled to the upper region of the rotator110.

The first power source is disposed outside the soak chamber10and comprised of a pneumatic cylinder111(referred to as a ‘first power source’ to be distinguished from a pneumatic cylinder which is a second power source discussed later). A piston rod111aof the first power source111is coupled to the first power transmitting shaft112R through a link111bin the tangent direction. In this embodiment, when the piston rod111amoves forward by the operation of the first power source111, the rotator110maintains a horizontal posture, and when the piston rod111amoves backward, the rotator110maintains a vertical posture. Here, the pneumatic cylinder is employed as the first power source111. A forward/backward rotating motor or a solenoid unit can also be used as the first power source111. The first power source111can be disposed in the soak chamber10. In this case, the environment of the soak chamber10may affect the operation or life span of the first power source111. Preferably, the first power source111is disposed outside the soak chamber10. A cylinder or motor having excellent high and low temperature characteristics and durability can be efficiently used as the first power source111installed in the soak chamber10. Such a cylinder or motor is expensive and will increase the cost of the test handler.

The first power transmitting shaft112R is rotatably installed through the wall of the soak chamber10, and formed in a hollow tube shape. The first power transmitting shaft112R is rotated by power supplied from the first power source111through the link111b, thereby transmitting a rotation force to the rotator110.

As illustrated inFIGS. 2 to 5, the stopper120is disposed at the front top region of the rotator110to be rotatable by about 90°. The stopper120includes an extended unit120ahaving its front end extended to be adjacent to the rear end of the test tray20, a hooking unit120bdisposed at the front end of the extended unit120aand rotated with the extended unit120a, for directly hooking the rear end of the test tray20completely entering the rotator110, and an eccentric protrusion unit120chaving an eccentric protrusion120c-1at the rear end of the extended unit120aas shown inFIG. 5in detail. The extended unit120aof the stopper120is fixed to the center portion of the top cover110-3through a support bracket120dto be rotatable in the forward or backward direction. When the extended unit120ais rotated, the hooking unit120bis rotated to hook or unhook the test tray20received in the rotator110. The eccentric protrusion120c-1is formed on the eccentric protrusion unit120cslantly from the rotation center of the extended unit120a. When the eccentric protrusion120c-1 is pushed or pulled, the extended unit120ais rotated. That is, a sliding block122ahaving a long hole122a-1on the second power transmitting shaft122serves as a cam, and the eccentric protrusion unit120cserves as a cam follower. This coupling structure will later be explained in detail.

The second power source is comprised of a pneumatic cylinder121(referred to as ‘second power source’ to be distinguished from the pneumatic cylinder which is the first power source), and disposed outside the soak chamber10. In this embodiment, the second power source121is installed in the side direction of the first power transmitting shaft112R outside the soak chamber10.

Still referring toFIGS. 2 and 3, the second power transmitting shaft122passes through the inside the first power transmitting shaft112R with the same axis center as that of the first power transmitting shaft112R. The second power transmitting shaft122is slidably mounted along the top cover110-3. In more detail, one side of the second power transmitting shaft122is extended to a piston rod side121aof the second power source121, and the other side thereof is extended to the inside of the soak chamber10. In addition, the second power transmitting shaft122has its one end coaxially arranged with and coupled to the piston rod121aof the second power source121(if necessary, the second power transmitting shaft122can be incorporated with the piston rod121a). The other end of the second power transmitting shaft122extended to the inside of the soak chamber10is fixedly coupled to the sliding block122ahaving the long hole122a-1for sufficiently receiving the eccentric protrusion120c-1of the eccentric protrusion unit120cof the stopper120. Accordingly, when the piston rod121amoves forward or backward by the operation of the second power source121, the second power transmitting shaft122and the sliding block122amove forward or backward to push or pull the eccentric protrusion120c-1, thereby rotating the stopper120. As a result, the test tray20held by the rotator110is hooked or unhooked by the hooking unit120b.

The flange130is fixedly coupled through the wall of the soak chamber10and formed in a hollow tube shape. The first power transmitting shaft112R passes through the flange130. Since the second power transmitting shaft122passes through the first power transmitting shaft112R, the first power transmitting shaft112R and the second power transmitting shaft122pass through the flange130.

The bearing140is positioned between the flange130and the first power transmitting shaft112R, for softly rotating the first power transmitting shaft112R.

The operation of the posture changing unit100will now be described with reference toFIGS. 6 to 10.

FIGS. 6 to 10are operational state views illustrating the posture changing process of the posture changing unit100, seen from VI direction ofFIG. 2according to an exemplary embodiment of the present invention.

At the initial stage, the rotator110of the posture changing unit100maintains a horizontal posture in the upper space of the soak chamber10(the piston rod111amoves forward), and the stopper120is rotated in the unhooking direction, thereby generating the state ofFIG. 6allowing entrance of the test tray20. Here, the test tray20on which the devices have been loaded by the loading unit enters the soak chamber10through a horizontal transferring unit (not shown).

That is, the test tray20horizontally enters the rotator110along the pair of entering rails110-1R and110-1L until the test tray20contacts the support stand110-2.

After the test tray20enters the rotator110, the second power source121is engaged, the second power transmitting shaft122slides into the soak chamber10, and the sliding block122aalso slides to push the eccentric protrusion120c-1. Therefore, the stopper120is rotated in the hooking direction by about 9020, thereby generating the state ofFIG. 7preventing separation of the test tray20. That is, the stopper120is hooked on the end of the test tray20, so that the test tray20can be stably positioned in the rotator110.

In the above state, when the first power source111is operated and the piston rod111amoves backward, as shown inFIG. 8, the rotator110is rotated by 90° around the idling shaft112L and the first power transmitting shaft112R, and the horizontal posture of the test tray20is changed into a vertical posture. The bottom end of the vertical posture test tray20is supported by a vertical move rail30. Because the second power transmitting shaft122is installed to pass through the first power transmitting shaft112R, even if the rotator110is rotated, if there is no artificial force, the state of the second power transmitting shaft122is maintained as it is.

As depicted inFIG. 9, when the test tray20supported by the vertical move rail30is sensed by a sensor (not shown), the second power source121is engaged again, and the piston rod121amoves backward. Therefore, the second power transmitting shaft122moves backward, and the stopper120is rotated in the unhooking direction by about 90°, thereby preparing an exit environment of the test tray20. In the above process, the test tray20is pre-heated/pre-cooled mainly by the first temperature control unit150.

As illustrated inFIG. 10, during the vertical move rail30is lowered, the test tray20is also lowered by a self weight. Thereafter, the test tray20is translated to the lower portion of the soak chamber10by a translating unit40(refer toFIG. 1), and sufficiently pre-heated/pre-cooled mainly by the second temperature control unit180.

On the other hand, when it is confirmed that the test tray20has completely exited from the rotator110, the first power source111is engaged again, and the piston rod111amoves forward. As shown inFIG. 6, the posture of the rotator110is changed into a horizontal posture. Accordingly, a new test tray20on which devices have been loaded can enter the rotator110.

By repeating the above process, the test trays20on which the devices have been loaded are carried into the lower space of the soak chamber10. While the test trays20are translated closely to a test chamber (not shown) by the translating unit40to be sequentially received, the pre-heating/pre-cooling is performed thereon. As a result, before entering the test chamber, the test trays20are sufficiently pre-heated/pre-cooled.

That is, as described above, the pre-heating/pre-cooling can be performed during the process of changing the posture of the test tray20or the process of moving the posture-changed test tray20to the downward direction, thereby reducing a translation distance D (refer toFIG. 1) of translating the test tray20on which the test objects, namely, the devices have been loaded to the test chamber side (left side ofFIG. 1), and obtaining the sufficient pre-heating/pre-cooling time of the devices. A margin space obtained by a margin length E (refer toFIG. 1) due to a reduction in the translation distance D can be used as an installation space for other devices. Even if the test tray20is enlarged, the whole size of the test handler is not seriously changed.

An operation method of the test handler according to an exemplary embodiment of the present invention will now be summarized with reference toFIG. 11.

The devices of the user trays are loaded onto the horizontal posture test tray.

After the devices are loaded, the horizontal posture of the test tray is changed into the vertical posture while being pre-heated/pre-cooled.

The vertical posture test tray is translated closely to the test chamber in the vertical posture while being pre-heated/pre-cooled.

The devices loaded on the test tray transferred to the test chamber having the test environment where the devices are tested.

5. Restoration, translation and posture change (S950)

After the test, the test tray is translated far from the test chamber in the vertical posture with the hot or cold devices being restored to the normal temperature, and the vertical posture of the test tray is changed to the horizontal posture.

The devices loaded on the horizontal posture test tray are sorted and unloaded to the user trays according to the test results.

According to the foregoing method, the pre-heating/pre-cooling is performed during the vertical posture change of the test tray, thereby reducing the pre-heating/pre-cooling time and the overall test time.

As described above, certain exemplary embodiments of the present invention provides the following advantages.

First, the test tray on which the test objects, namely, the devices have been loaded is held and posture-changed by the posture changing unit disposed in the soak chamber, in more detail, the rotator disposed in the soak chamber. While the test tray is posture-changed or until the test tray is stably positioned in the translating unit after the posture change, the devices are continuously pre-heated/pre-cooled. Therefore, the overall test time of the devices can be reduced.

Second, the test tray can be enlarged without increasing the whole size of the test handler, by changing the horizontal posture of the test tray into the vertical posture in the soak chamber and decreasing the translation distance.

Third, the rotator or the stopper is installed inside the soak chamber, and the power sources for operating the rotator or the stopper are installed outside the soak chamber, so that each power source cannot be affected by the inside environment of the soak chamber. As a result, the test tray is posture-changed in the soak chamber without deteriorating the life span or operational state of the power sources by the environment of the soak chamber.