EV Specifications, Facts and Tips, Parts Names
Electronic Visions 620 Aligner/501 Bonder
Overview: (specifications, facts and tips, parts names)
Specifications for 501 Bonder
- Max substrate stack thickness 4.5mm
- Max over pressure 2bar
- Standard vacuum 5E-3 mbar
- High vacuum 1E=5 mbar
- Max temperature 550 deg C, in 1 deg C steps
- Temperature uniformity +- 1% (+- 0.5% optional)
- Voltage supply 0-1200V, 50 ma (optional up to 3000V
- Contact force 3400N (765lbf), with options of 7000N or 40000N (hydraulic)
Specification for 420 aligner
- Alignment range in X and Y directions +-5mm, Theta +_3.5 degrees.
- Alignment accuracy: mask alignment 0.5um top side, 1.0um front to back; bond alignment 0.5um glass to silicon, 1.0um silicon to silicon (with 20x objective, ours is 10x so these numbers should be doubled).
- Max separation (during alignment) 300um adjustable in 1um steps.
- Objectives available: 3.6x, 4x, 5x, 10x (we have this), 20x
- Total magnification 130x - 725x available (we have ~362x).
- Top side objective travel range: x direction 30 - 150mm separation (8 - 150mm optional); y direction +-75mm; z direction +-5mm
- Bottom side objective travel range: x direction 30 - 100mm separation (8-100mm optional); y direction +-12mm, z direction +-5mm.
- Lamp house; standard NUV 350-450nm, standard power 200W to 500W, optional 1000W.
Facts and Tips on 620 Aligner
- It is possible to store the positions of the objectives and return to the positions using the "Set" and "Train" functions in the EV620 menu.
- Vacuum contact will typically yield the best resolution, followed by hard contact, soft contact, and finally proximity.
- The stage should be centered
with the micrometers before the start of any alignment process. This ensures
that the mask will be centered on the mask holder, or the wafer will be
centered on the bond tool or the chuck. This is especially important during bond alignment and back side alignment also make sure that the wafer covers the vacuum groove on the bond tool.
- The vacuum is transferred to the bond tool frame and bond tool or mask holder through o-rings at the back of the cover. The bond tool or mask must be pushed all the way back in the holder to make good vacuum contact. No vacuum grease should be used.
- There is an option in the microscope parameter menu to choose either normal or flat objectives. If you are having difficulty moving the objectives to your alignment keys, switching the objective settings may give the objectives more range.
- The chuck weight LCD readout should read about 300 (270 to 300 range).
Facts and Tips on the EV501 Bonder
- It is possible to switch the units that the software uses by selection "Options" and then "units". The two choices are: mbar for chamber pressure and Newtons for contact force OR torr for chamber pressure and pounds force for contact force (we use the first option). The choice of units is not stored in the recipe file, and should be verified in the "Options" menu before bonding.
- There are green LEDs on the side of the bonder that indicate illumination of the heating lamps. One LED is for the top side heater, and two are for the bottom side heater (there are two circuits for the bottom).
- There are also two green LEDs near the main heater switch on the electronics rack, indicating that a signal is being sent to the heater lamps.
- A common cause of the "low vacuum" error during bond alignment is loose mounting screws for the bond tool insert. These screws can become loose during repeated thermal cycling, and need to be tightened periodically.
- There is a thermocouple in the bottom heater chuck, one in the top heater, and one that makes contact with the bond tool. The software offers the choice of using either the bottom chuck thermocouple or the top thermocouple. The bottom chuck thermocouple is the one that is normally used, especially when bonding in an evacuated chamber.
- The pressure converter window is used for extremely precise control of the contact force. The user must enter the pressure under which the chamber will be during bonding. This allows the software to compensate for any pressure differential between the chamber and the facility ambient.
- The "S" button on the record file chart can be used to configure the chart. The current, voltage, temperatures, and chamber pressure can be set to record or not, and the state lines can be set to show the state of any three of the pump, purge, piston, voltage, or wafer bow.
- The range of the current that the record file records can be set to either 9 or 5 mA or 0 to 50 mA by clicking on the current (I) button.
- The record file can be opened in Microsoft Excel or another spreadsheet program, and customized graphs can be made from the data.
Official Electronic Visions part names:
- Bond tool/chuck top - The tool onto which the aligned wafers are clamped and transferred to the bonder
- Bond too/chuck bottom - The tool that swings out of the EV420 to load wafers for bonding
- Bond tool frame - The outside part of the bond chuck top, usually aluminum
- Bond tool insert - The inside part of the bond chuck top that has the vacuum groove; can be steel, Teflon, graphite, or other materials
- Quartz pressure plate - The circular quartz plate that is attached to the cover of the bonder, with a cutout in the center for the wafer bow pin
- Cover electrode - The thin electrode that is attached to the cover of the bonder, and on top of the quartz pressure plate
- Bond glass - The piece of quartz that is used to clamp the wafers to the bond tool top
- Graphite/Teflon/Steel disc - The disc that is placed inside of the bond glass
- Wafer bow pin - The (usually ceramic) pin that makes contact with the wafers first when the piston comes down in the bonder.
- Bottom heater chuck - The metal chuck on which the bond tool top sits in the bonder
- Absorber disc - The cone shaped piece in the cover of the bonder onto which the top side heating lamps shine
- Mask holder - The glass frame that holds the mask using vacuum in the EV420
- Lithography chuck bottom - The tool that swings out of the EV420 to load wafers for lithography
- Mask loading frame - The thin square black frame that is used to position the mask for loading
- Cover - The upper part of the EV420 that moves up and down pneumatically; it holds the mask holder of the bond tool top.
- Tray - The par of the EV420 that swings out, and hold the bond chuck bottom or lithography chuck bottom
- Stage - The bottom part of the EV420 that moves during alignment with the micrometers