S-Cubed Flexi - Operating Procedure

Work In Progress This article is still under construction. It may contain factual errors. Content is subject to change.

Only staff & designated maintenance users are allowed to write recipes on this tool!  
Maintaining low particle counts on this tool is extremely important, so users must strictly follow the training procedures. The Underside of your wafers must be clean to avoid contamination!

Procedure:

1. Check if the correct user account is selected. Only use the “UCSB User” account.
   1. Click “Home” -> “Change User”. User Name: “UCSB Users”, Password: “ucsb”
2. Make sure the system is not running a process. Lot view shows no wafers or batches running.
3. Check if PR containers are empty. PR bottles that are available to use are UV6-0.8 in POD#4 and DSK101 in POD#5. If bottles are empty (if you see large bubbles in the supply tube) use the “report tool issue” in signupmonkey. Users are not authorized to change or add any chemistries.
4. Check the PR nozzle “bath” (small white tray underneath Arm 1). Make sure it’s not clogged (should have a bit of liquid, but not above the drain hole). If the bath is clogged use the “report tool issue” in signupmonkey. Users are not authorized to clean the nozzle bath or the nozzle tips. To unclog or clean, the robot arms need to be raised up. Or else nozzles can get bumped and change its positions. Only staff is allowed to manually raise the robot arm and clean the nozzle tips & bath.
5. Make sure all wafers to be used in the S-Cube have extremely clean backsides. If wafers have dirt, clean the backside following the steps given in the “How to clean wafer backside before use” section, before using in the S-Cube.
6. Check if hot plates are set to required temperatures for your process. If not, run Temp-change recipes:
   1. Note only Hot Plate 4 (HP4) temperature can be changed. HP1(135C), HP2(170C) & HP3(170C) temperatures are set and cannot be changed.
   2. Load dummy wafer (With extremely clean underside)
   3. Run Staff -> HP4-SET-***C recipe. HP4 can be set to 185C, 200C, 210C or 220C.
      1. Ex: HP4-SET-220C will set hot plate 4 to 220⁰C
   4. Check that the hotplate reaches the desired temperature (will overshoot by ~2C - 3C).
   5. After 5 min wafer bake, make sure the temperature is ±2C before running the actual process.
7. Load a test “mechanical” wafer (With extremely clean underside) and run a test run of your desired recipe and make sure spin looks ok. This is important for the first UV6-0.8 run after more than 6 hrs of idle time. The 1^st mechanical test wafer will likely show radial non uniformity as dried PR is ejected. 2^nd test wafer should spin with high uniformity. If the nozzle is clogged, report tool issue in signupmonkey.
8. Load your wafers into the left Cassette at Load Port 1 (LP1 labeled with “1”).
9. Select the Route/Chain to run (see available recipes table).  Use filter [staff] for all the available routes.
10. Select wafer slots to run in the LP1 section
11. Click [Run] to run your route. Do not open the tool door while process is running.

Process currently available to lab users:

• Coat DSK at:
  • Varying speeds (1.5 & 5 krpm)
  • Varying temperatures (185C, 200C, 210C, 220C)
• Coat UV6-0.8 at:
  • Varying speeds (2, 2.5, 3, 3.5, 4, 5 & 6 krpm)
  • Single temperature (135C)
• Combination of the above two:
  • DSK @ 1.5K or 5K @ 220C + UV6 @ 2K – 6K @ 135C
  • DSK @ 1.5K or 5K @ 185C + UV6 @ 2K – 6K @ 135C
• PEB Bake at 135C for 90 sec
• Develop at single spin speed of 300 rpm and varying develop time (10, 15 & 20 sec)
• Combination of PEB bake and develop: Bake @ 135C 90sec + Develop @ 300rpm @ 10 – 20 sec
• DO NOT run developer recipes that are not in "UCSB Users"!  There are experimental Develop recipes in the other logins that can damage and bring tool down for extended period of time!

Troubleshooting:

1. Air bubbles in the PR, EBR-PG or AZ300MIF tubes.
   1. Use [Report Tool issue] on SignupMonkey to report the problem & get help.
2. If PR nozzle bath (small white tray underneath Arm 1) or the nozzle tip is clogged.
   1. Use [Report Tool issue] on SignupMonkey to report the problem & get help.
   2. Users are not authorized to manually raise the nozzle tips and clean them.
3. Robot arms are not moving after 5min – 10min after starting a route.
   1. Use [Report Tool issue] on SignupMonkey to report the problem & get help.
   2. Tool may need full system reset. Users are not allowed to manually initialize the tool.
4. If wafer is lost in tool.
   1. Use [Report Tool issue] on SignupMonkey to report the problem & get help.
   2. Do not try to retrieve the wafer on your own.
5. The Run button cannot be toggled after clicking “no” at “Run Selected Route” prompt in LP1.
   1. Physically remove the black wafer carrier from LP1 and wait for 2 sec.
   2. Put the wafer carrier back in its place in LP1.
   3. LP1 tabs in the Run section will get re-initialized.
6. Unknowingly ran a developer recipe not in “UCSB Users” login.
   1. As a precaution, DO NOT run developer recipes that are not in "UCSB Users" login!
   2. Notify staff immediately!
7. If new or other variations of standard recipe is needed, contact staff.

How to clean wafer backside before use:

1. Place the wafer upside down in the POLOS spinner using a non-contact chuck.
2. Set spin speed to 2000 rpm. Program “backside”.
3. Spin wafer, wait until at top speed.
4. Squirt “Remover PG” 10 sec, then Acetone 3 seconds, then ISO for 3 sec
5. Spin Dry while blowing with N2. Wait ~5 sec before stopping spin.

Available PR Spin Recipes

Recipes > Lithography > Automated Coater Recipes - See all available spin-coat recipes for this machine. Only Staff may edit/create recipes.