Wafer test method with probe card having on-board multiplex circuitry for expanding tester resources
First Claim
1. A method for testing a semiconductor wafer containing a plurality of dice having a plurality of die contacts comprising:
- providing a tester configured to transmit test signals to the dice on the wafer;
providing a probe card comprising a plurality of probe card contacts in electrical communication with the tester, the probe card contacts arranged in sets configured to electrically engage selected dice on the wafer;
providing a multiplex circuit on the probe card in electrical communication with the probe card contacts and configured to selectively enable and disable the probe card contacts;
placing the probe card contacts in electrical communication with the die contacts on the wafer; and
using the multiplex circuit to control the test signals to fan out the test signals to the probe card contacts, to selectively transmit the test signals to the die contacts while the sets maintain a uniqueness of each die, and to disconnect defective dice.
0 Assignments
0 Petitions
Accused Products
Abstract
A probe card, a test method and a test system for testing semiconductor wafers are provided. The test system includes the probe card, a tester for generating test signals, and a wafer prober for placing the wafers and probe card in physical contact. The probe card includes contacts for electrically engaging die contacts on the wafer. The probe card also includes an on board multiplex circuit adapted to fan out and selectively transmit test signals from the tester to the probe card contacts. The multiplex circuit expands tester resources by allowing test signals to be written to multiple dice in parallel. Reading of the dice can be performed in groups up to the limit of the tester resources. In addition to expanding tester resources, the multiplex circuit maintains the individuality of each die, and permits defective dice to be electrically disconnected.
-
Citations
16 Claims
-
1. A method for testing a semiconductor wafer containing a plurality of dice having a plurality of die contacts comprising:
-
providing a tester configured to transmit test signals to the dice on the wafer;
providing a probe card comprising a plurality of probe card contacts in electrical communication with the tester, the probe card contacts arranged in sets configured to electrically engage selected dice on the wafer;
providing a multiplex circuit on the probe card in electrical communication with the probe card contacts and configured to selectively enable and disable the probe card contacts;
placing the probe card contacts in electrical communication with the die contacts on the wafer; and
using the multiplex circuit to control the test signals to fan out the test signals to the probe card contacts, to selectively transmit the test signals to the die contacts while the sets maintain a uniqueness of each die, and to disconnect defective dice. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method for testing a semiconductor wafer containing a plurality of dice having a plurality of die contacts comprising:
-
providing a tester configured to transmit a write test signal to the dice;
providing a probe card comprising a plurality of probe card contacts in electrical communication with the tester, the probe card contacts arranged in sets configured to maintain a uniqueness of each die on the wafer;
providing a multiplex circuit on the probe card configured to control the test signals to fan out the write test signal into multiple write test signals and to selectively enable or disable the probe card contacts;
placing the probe card contacts in electrical communication with selected die contacts on the wafer;
writing the multiple write test signals to at least some of the selected die contacts at a same time by selective actuation of the probe card contacts;
reading a plurality of read test signals from the selected die contacts in groups by selective actuation of the probe card contacts; and
disabling at least some of the probe card contacts to disconnect any defective dice. - View Dependent Claims (7, 8)
-
-
9. A method for testing semiconductor dice contained on a wafer comprising:
-
providing a tester comprising a test circuitry configured to generate and transmit write test signals to the dice and to analyze read test signals from the dice, the tester having tester resources determined by a signal generating, transmitting and analyzing capability of the test circuitry;
providing a probe card comprising an on-board multiplex circuit and a plurality of probe card contacts in electrical communication with the multiplex circuit and the tester, the mulitplex circuit configured to control the test signals to speed up the testing, by fanning out the write test signals to multiple dice, and by reading the read test signals in groups up to a limit of the tester resources;
placing the probe card contacts in electrical communication with die contacts on selected dice;
writing the write test signals to the selected dice at a same time; and
reading the read test signals from the selected dice. - View Dependent Claims (10, 11)
-
-
12. A method for testing semiconductor dice contained on a water having a plurality of die contacts comprising;
-
providing a tester having a signal writing capability and a signal reading capability;
providing a probe card comprising a multiplex circuit and a plurality of probe card contacts in electrical communication with the multiplex circuit and the tester;
placing the probe card contacts in electrical communication with the die contacts on selected dice; and
using the multiplex circuit to control the test signals to expand the signal writing capability of the tester, and to speed up the testing, by multiplexing write test signals from the tester to the die contacts on the selected dice, by reading read test signals from the selected dice in groups up to the signal reading capability, and by controlling the probe card contacts to disable defective dice. - View Dependent Claims (13, 14, 15, 16)
-
Specification