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| BEFORE | AFTER | |
| Vacuum Chamber PM Technique | ||
| Kokusai Vertical Diffusion Furnace Door Assembly | ||
| OBJECTIVE: | ||
| TO EFFECTIVELY PM THE VERTICAL DIFFUSION FURNACE DOOR ASSEMBLY IN A TIMELY MANNER, WHILE IMPROVING TOOL RECOVERY AND PARTICLE PERFORMANCE | ||
| Vacuum Chamber: | KOKUSAI VERTICAL DIFFUSION FURNACE | |
| Vacuum Chamber Process Residue: | PROCESS INDUCED RESIDUE | |
| Vacuum Chamber Components: | KOKUSAI VDF DOOR ASSEMBLY |
| Old Procedure: | Infrequent cleaning at outside parts clean shops | |
| Solvent: | DI water, IPA (only) | |
| Vacuum Chamber Products: | |||
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| **Various Diamond Grit abrasives can be selected for this process depending on the amount of deposition build-up within the vertical diffusion furnace door assembly – range from 140 to 800 Diamond Grit available. Most PM’s can be performed with 280 or 360 Grit ScrubPADs and ScrubTIPS® but the use of more aggressive pads may be required for certain high current processes or on the first PM that is accomplished w/o H202 | ||||||
| NOTE: Depending on amount of deposition build-up and if the tool has been PM’d in the past, products may vary and/or additional products may be required | ||||||
| Kokusai Vertical Diffusion Furnace PM Procedure: | ||||||
| View “How to” instructional videos on http://www.foamtecintlwcc.com/video/ | ||||||
| Step 1: | Remove door assembly from tool and place on approved cleaning surface |
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Fig 1 & 2: Pedestal plate and pedestal door assembly as removed from the machine |
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Fig 3:ErgoSCRUB® - FT951, ScrubDISKS®- HT4518DC3, HT4536DC3 and HT4580DC3 for cleaning flat portions of the door and pedestal plate |
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| Step 2: | Using HT5790S and IPA; thoroughly wipe down the door and pedestal plate paying particular attention to ports, flanges, 90o corners as well as the seal ring and support ring | |||||
| Step 3: | For the flat surfaces on the door and pedestal plate, use FT951 ErgoSCRUB® and HT4518DC3-1 ScrubDISK® to scrub in process deposition using a circular motion, making sure to keep the pad and surface wet with DI water. Be sure to clean both the door and boat side of the pedestal plate | |||||
| Step 4: | As UltraSOLV® ScrubPAD or ScrubDISK® begins to load-up with deposition; it can be cleaned off by dragging across UltraSOLV® Sponge in one direction (See Fig 4, 5 & 6) |
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Fig 4: ScrubDISK® loaded with deposition |
Fig 5: Pull and Twist ScrubDISK® across UltraSOLV® Sponge |
Fig 6: Unloaded ScrubDISK® |
| Step 5: | Unload the UltraSOLV® HT4754 Sponge by rinsing out with DI water and ringing out into a HazMat container (See Fig 7 & 8) | ||||
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Fig 7: Loaded-up UltraSOLV® Sponge |
Fig 8: UltraSOLV® Sponge AFTER rinse |
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| NOTE: | AFTER THE INITIAL PM IT IS LIKELY THAT THE 280 GRIT DIAMOND ScrubDISK® CAN BE SUBSTITUTED FOR THE 180 GRIT DIAMOND ScrubDISK® |
| Step 6: | For areas of the plate and door not accessible with the ErgoSCRUB®, use the HT4518D 180 Grit Diamond ScrubPAD to scrub the deposition. Use the same circular motion being sure to keep the pad and surface wetted with DI water | ||||
| Step 7: | To clean the pedestal mount and the mounting slot, the ScrubPAD may be cut into strips (See Fig 9a) | ||||
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Fig 9b:ScrubTIPs® HT179018D-1, HT179036D-1 and HT179080D-1 were used to clean the ports, cutouts and 90o articulated surfaces on the pedestal plate |
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| Step 8: | For ports, cutouts, 90o corners and other articulated portions of the pedestal plate, the initial scrubbing should be done with the ScrubTIPS® HT179018D, HT173218D and the HT174918D (See Fig 9b, 10a and 10b) | ||||
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| NOTE: | AS WITH THE ScrubPADS AND ScrubDISKS®, THE HT4754 SPONGE CAN BE USED TO CLEAR THE BUILD-UP SLUDGE FROM THE ScrubTIP® | ||||
| Step 9: | Polish all surfaces scrubbed with the 180 Grit Diamond ScrubDISK®, ScrubPADS and ScrubTIPS® by using the same DISK, PAD or TIP in the 360 grit and then the 800 grit. For example, all the flat surfaces previously scrubbed with the 180Grit Diamond ScrubDISK® should be polished successively with the 360 grit and 800 grit (See Fig 11a) | ||||
| Step 10: | The door of the pedestal mount should be cleaned according to Fig 11a. The flat portions should be scrubbed with the HT179036D ScrubTIP® and polished with the HT179080D ScrubTIP®. The recessed channel and orifice should be scrubbed with the HT174936D and the HT173236D and polished with the HT174980D | ||||
It is recommended to pre-clean the scrubbed areas with the HT4754 sponge prior to moving to the higher grit PAD, DISK OR TIP. For corners, ports and other areas not easily accessed with the sponge a MiraWIPE® wrapped around an appropriately sized swab will expedite this pre-cleaning process |
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| The channel and orifice should be cleaned with the HT1749 UltraSOLV® Swab with IPA. It is also recommended to wrap a HT5790S MiraWIPE® around the end of the swab to final clean the 4 channels on the top of the pedestal mount (See Fig 11c) | |||||
The o-ring grove should be thoroughly polished with the HT179080D ScrubTIP® and then cleaned with the HT1790 UltraSOLV® Swab. Final cleaning should be accomplished by wrapping the MiraWIPE® around the end of the HT1790 Swab and wetting it with IPA (See Fig 11c) |
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| The thermal couple (TC) port should not be scrubbed. To clean the TC port use the HT1790 UltraSOLV® Swab followed by a MiraWIPE® wrapped round the swab as described above (See Fig 11c & 12) | |||||
 Door bellows
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Fig 11a: HT179036D-1 and HT179080D -1 ScrubTIPS® followed by HT1748 and HT1749 UltraSOLV® Swabs to clean the top surface of the door bellows |
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| Step 11: | Final cleaning should be accomplished using MiraWIPE® dampened with IPA and the appropriately shaped swabs as denoted in the various pictures. Make sure to use fresh wipers until visible contamination ceases to transfer from the part to the wiper | |||
| Special attention should be given to articulated areas and especially the 90o corners. Wrapping the MiraWIPE® round the appropriately shaped swabs will ensure the part is as clean as possible | ||||
| The TC port in the door is especially dirty and should be cleaned with 2-3 HT1790 swabs and then finished with a MiraWIPE® wrapped round a HT1701 Swab | ||||
| FINAL WIPE PROCEDURE: | ||
IMPORTANT NOTE |
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| THE USE OF HT5790S MiraWIPES® DURING THE FINAL WIPE PORTION OF THE PROCEDURE IS A CRITICAL STEP TO EFFECTIVELY REMOVE PARTICLE DEFECTS | ||
| Figure below shows how much more deposition the Foamtec International MiraWIPE® can remove from a critical surface compared to the standard fab wiper, making the MiraWIPE® FINAL WIPE PROCEDURE the most CRITICAL STEP of the PM procedure (See Fig 10a & 10b) | ||
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Fig 13: Post Clean Flange Assembly: Current wiper was used to verify cleanliness of the flange assembly as received from parts clean vendor. Assembly was declared clean, as no contamination was transferred from the flange to the wiper |
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MiraWIPES® are the KEY STEP for DEFECT REDUCTION and IMPROVED TOOL RECOVERY |
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Fig 14: HT5790S MiraWIPE® was used to further clean the flange assembly. Note contamination transferred to MiraWIPE® after part was first cleaned with a POR Wiper. |
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Fig 17 & 18: Door assembly, post PM |
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Parts Used During PM |
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