Classifying – separating – and assorting solids – Sorting special items – and certain methods and apparatus for... – Condition responsive means controls separating means
Reexamination Certificate
1999-03-24
2001-05-29
Nguyen, Tuan N. (Department: 3653)
Classifying, separating, and assorting solids
Sorting special items, and certain methods and apparatus for...
Condition responsive means controls separating means
C209S933000, C324S1540PB
Reexamination Certificate
active
06239396
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor burn-in process and, more particularly, to an apparatus for inserting, removing, and sorting semiconductor devices according to the results of tests.
2. Description of the Related Art
In order to identify devices that are likely to fail in their early life, semiconductor devices after fabrication undergo testing or screening that applies electrical and thermal stresses to the devices and identifies devices having the potential for early failure. Generally, a process for screening the semiconductor devices is called a “semiconductor device burn-in test.”
A monitoring burn-in test (MBT) chamber for the burn-in tests requires a semiconductor device handling and sorting apparatus or system which sorts semiconductor devices in accordance with the burn-in test results. The apparatus inserts semiconductor devices into a burn-in board for testing, removes tested semiconductor devices from the burn-in board, and sorts the tested semiconductor devices into good and failed categories. Such an apparatus typically includes various tools for rapidly performing the sorting operation.
For example, one conventional device handling and sorting apparatus includes a centering pocket unit, a DC test unit and a carrier pocket unit disposed in line on a stage of the apparatus. A burn-in board containing tested semiconductor devices thereon is disposed under the stage. A center portion of the stage has an opening so that the burn-in board moving in an XY-plane under the stage can be accessed through the opening. Thus, the burn-in board can be smoothly positioned for operations connected with various tools on the stage. Multiple transportation tools, which are driven by a driving cylinder, are in respective upper portions of the centering pocket unit, the DC test unit and the carrier pocket unit. The transportation tools transport the semiconductor devices rapidly and stably between the units.
In the conventional apparatuses such as described above, when a burn-in board having the burn-in tested semiconductor devices thereon is loaded to a lower portion of a stage, a transportation tool removes the semiconductor devices from the burn-in board and loads the semiconductor devices on the carrier pocket unit. From the carrier pocket unit, the transportation tool transports only good devices to an unloading tray positioned at an unloading terminal unit. Then, the carrier pocket unit which contains the remaining failed devices moves toward a rear portion of the stage, sorts the remaining failed devices into several levels, and loads the devices on burn-in rejecting trays according to the levels.
In order to prepare a semiconductor device for a burn-in test, a transportation tool loads the semiconductor device from a loading tray on a loading terminal to the centering pocket unit, aligns the semiconductor device, and transports the aligned semiconductor device to a DC test unit for a DC test of the semiconductor device prior to inserting the semiconductor device into a burn-in board. If the semiconductor device passes the DC test, the transportation tool plugs the semiconductor device into the burn-in board. However, if the semiconductor device fails the DC test, the transportation tool loads the semiconductor device into a DC rejecting tray. The DC rejecting tray is in the vicinity of an XY-table positioned under the stage, and moves in XY-plane under the stage so as to receive the DC test-rejected semiconductor devices.
To summarize, after unloading and sorting the semiconductor devices that are burn-in tested in the MBT chamber, the device handling and sorting apparatus loads semiconductor devices that passed the DC-test into an empty burn-in board and transports the burn-in board loaded with semiconductor devices to the MBT chamber for a new burn-in test.
Conventional device handling and sorting apparatuses have some problems. For example, burn-in tests and sorting of the semiconductor devices into good product or failures according to the results of the DC test are performed simultaneously. Therefore, respective tools related to good devices and rejected devices can collide because the tools move on the same operation line. In addition, an operation of the burn-in rejecting trays requires an XY-robot in addition to a robot that operates the transporting tools. The use of the two robots may complicate control of the apparatus, so that unexpected operation errors may occur. Moreover, operation of the DC rejecting trays may aggravate the operation errors. If the XY-table moves too frequently, a small impact can pop the semiconductor devices in the DC rejecting trays out of the DC rejecting trays. Further, a transportation tool may wait for a considerable time above the stage until the DC rejecting trays are properly positioned. As a result, overall operating efficiency of the apparatus is lowered.
SUMMARY OF THE INVENTION
An embodiment of the present invention provides a semiconductor device handling and sorting apparatus. The apparatus transports the semiconductor devices rejected from DC and burn-in tests separately from a main operation of the apparatus and without using an XY-robot and XY-table. The apparatus is not forced to wait for an aligned positioning of the DC rejecting trays before loading the rejected devices to the trays, so that the operating efficiency of the apparatus is high. In short, an overall architecture of the apparatus is simple and increases the operating efficiency of the apparatus.
In one embodiment, the apparatus includes separate device handling units respectively for good and rejected semiconductor devices. Further, a DC rejecting tray and a burn-in rejecting tray are integrated and disposed in the vicinity of a stage, so that the integrated DC and burn-in rejecting tray moves on a movable plate near the stage. Here, transportation paths of semiconductor devices are perpendicular to a path of the movable plate.
The apparatus further includes a DC test unit and a carrier pocket unit disposed to move back and forth on the stage. The DC test unit and a carrier pocket unit move to the back of the stage when the units are to unload rejected devices. Accordingly, a transportation path of the rejected devices is separated from a transportation path of the good devices.
As a result, respective subsequent handling of the rejected and good devices, such as loading of the good devices in a burn-in board or an unloading tray and loading of the rejected devices into a rejecting tray, can be performed simultaneously without interfering each other.
REFERENCES:
patent: 3662881 (1972-05-01), Fineran
patent: 4128174 (1978-12-01), Frisbie et al.
patent: 4348276 (1982-09-01), Tateishi et al.
patent: 4871963 (1989-10-01), Cozzi
patent: 4908126 (1990-03-01), Willberg et al.
patent: 5230432 (1993-07-01), Sugai
patent: 5848705 (1998-12-01), Gianpaolo et al.
patent: 5865319 (1999-02-01), Okuda et al.
patent: 6-9007 (1994-01-01), None
patent: 92/04989 (1992-04-01), None
Heid David W.
Nguyen Tuan N.
Samsung Electronics Co,. Ltd.
Skjerven Morrill & MacPherson LLP
LandOfFree
Semiconductor device handling and sorting apparatus for a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor device handling and sorting apparatus for a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor device handling and sorting apparatus for a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2540090