Transcript ppt-file - ladders

Measuring Leakage Current on Singles and Ladders
P. Riedler and S. Ceresa, August 2005
Needle for sensor back side contact
Manipulator
Sensor
Chip
Probe-card with contact needles for chip
• Apply +50V on sensor back
side via needle
• Ground sensor front side via
chip contacts (-> probe-card)
Sensor back side
Probe-card needles
Probe-card
Manipulator arm with needle
Check-list:
• The probe-card is installed correctly.
• Cables J1 and J2 are connected to the probe-card and on the other
side to the MB card. The connectors on the cables are labeled as well
as the connectors on the probe-card. On the MB side the connector
names are on the large PCB: J1=J1, J10=J2.
• The 5 cables from the MB card should be connected to the Gossen
power supply.
• The manipulator coax cable should be connected to the filter (lemo
connectors with capacitors and resistor).
• The filter should be connected on one side to the Keithley (inner
conductor=> +, outer conductor => -) and on the other side to the lemo
cable soldered to the probe-card.
The probe-card is connected via cables J1+J2 to the MB card. The
MB card is connected to the Gossen power supply:
Cables J1+J2
Probe-card
MB card
Contacting the chip
After the first contact the chuck needs to be moved up by ~ 80-100
microns to ensure a good electrical contact:
1st contact:
Needles barely touch the pads
Good el. contact (1st contact + 80 microns):
Needle marks are clearly visible
Chuck settings:
SET ALIGN to -500 microns (important to avoid damage to the
probe card!).
SET SEPARATION to -1000 microns.
Once the contact point is found the CONTACT should be SET.
The same contact setting can be used for all chips unless the
prober is switched off in between.
Gossen Power Supply (Chip):
Cables
MB card
After contacting the chip with the
probe-card needles the power supply
can be switched on:
-5V
~ 100mA
+5V
~ 600mA
+5V
~ 1A
The cables should be connected
correctly and the three outputs
should be adjusted to 5V (checked
April 05).
The expected current consumption
of the 3 outputs is indicated above.
Gossen power supply
with cables to the MB card
Sequence - SWITCH ON:
•
Position single/ladder on vacuum chuck.
•
Contact the pads of the chip with the probe-card needles (see previous
slides).
•
Contact the back side of the sensor with the manipulator needle.
•
Switch on the Gossen 3x5V power supply.
Sequence - SWITCH ON … continued:
•
Switch on the PC and VME crate
•
Start “ALICE PTS” Labview program located on the desktop.
•
Select “Initialize” and “Initialize VME” from the menu of the ALICE
PTS window. This will start the VXI resource manager. Once it
finished, click OK.
•
Go back to the ALICE PTS window and click “Initialize JTAG” and
“Initialize MB”. A red LED on the MB card will come on.
•
Switch on the Keithley 2410.
•
Increase the bias voltage (Keithley) up to 50V and measure the leakage
current (Keithley).
Sequence - SWITCH OFF:
Warning: do not disconnect the needles with the
power supplies switched on!
1.
Decrease the bias voltage (Keithley) to 0V.
2. Switch off the Keithley 2410 power supply.
3. Switch off MB card using black switch on the PCB.
4. Switch off the Gossen 3x5V power supply.
5. De-contact the manipulator needle.
6. De-contact the chip by moving into “ALIGN position”.