Automated loading/unloading of devices for burn-in testing
View Patent ↗The automatic loading and unloading of devices for burn-in testing is facilitated by loading burn-in boards in a magazine with the stacked boards in the magazine moved into and out of a burn-in oven by means of a trolley. The trolley can include an elevator whereby a plurality of magazines can be stacked in the oven for the simultaneous burn-in testing of devices mounted on the burn-in boards. Each board has rollers on one end which are engagable by pneumatically actuated cam mechanisms for inserting the board into an electrical contact in the oven for burn-in tests. Preferably, the cam mechanisms allow for extraction of a single board for inspection.
1. A method of transporting semiconductor devices on burn-in boards between a board Load/Unload Station and an oven for burn-in tests comprising the steps of:
a) providing a carrier for supporting a plurality of boards in a stacked array;
b) stacking boards in the carrier at the Load/Unload Station with semiconductor devices sequentially loaded into each board;
c) transporting the carrier and boards to the burn-in oven;
d) placing the carrier and boards into the oven with electrical contacts on each board abutting electrical connectors of the burn-in oven; and
e) sliding the boards and contacts into engagement with the connectors for the performance of burn-in tests on the semiconductor devices with a mechanism in a door of the oven which engages the boards and slides the board contacts into engagement with the connectors.
2. The method of claim 1 wherein each board includes a plurality of rollers at one end of the board opposite from the electrical contacts at another end of the board, the mechanism including cam surfaces which receive the plurality of rollers and drive the boards through the rollers when the cam surfaces are slid on the rollers by pneumatic actuation.
3. The method of claim 1 wherein the mechanism is pneumatically actuated.
4. The method of claim 2 wherein step c) includes use of a trolley which abuts the Load/Unload Station for receiving a carrier with stacked boards and abuts the oven for placing the carrier and boards into the oven in step d).
5. The method of claim 4 wherein the trolley, the oven, and the Load/Unload Station have rollers to facilitate the movement of a carrier with stacked boards to and from the carrier.
6. The method of claim 5 wherein in step d) the trolley has an elevator for placing a plurality of carriers in a stack in the Load/Unload Station and in the oven.
7. The method of claim 6 and including the step of horizontal alignment of the carrier with the oven and with Load/Unload Station by a physical alignment mechanism of the trolley and vertically aligning the carrier with the oven and the Load/Unload Station by an optical alignment mechanism in the carrier.
8. The method of claim 1 wherein step c) includes use of a trolley which abuts the Load/Unload Station for receiving a carrier with stacked boards and abuts the oven for placing the carrier and boards into the oven in step d).
9. The method of claim 8 wherein the trolley, the oven, and the Load/Unload Station have rollers to facilitate the movement of a carrier with stacked boards to and from the carrier.
10. The method of claim 9 wherein in step d) the trolley has an elevator for placing a plurality of carriers in a stack in the Load/Unload Station.
11. The method of claim 1 wherein the mechanism allows for retraction of a single board for inspection.