Welcome to all the clean-room users!
A cleanroom is full of hazard and danger, thus to minimize the occurence of accident and, if one does happen, to minimize its effects, some common sense rules have to be followed. Here are they!
Obviously such regulation change from time to time to reflect the improved understanding of the hazards of the cleanroom, thus, please, do check this page again in the future.

Clean-room regulation

Please ensure that all the below mentioned rules and regulations are followed. Offenders will be sanctioned by the MML 1 Professor in Charge and the Safety Coordinator depending on the gravity of the infraction.

  1. Cleanroom operation hours :
    • 9:00 am to 17:00 (Monday to Thursday)
    • 9:00 am to 16:30 (Friday only)
    • 9:00 am to 12:00 (Eve of Public Holiday e.g. New Year,Chinese New Year and Christmas only)
    • none (Saturdays, Sundays & public holidays )
    The period of time from 8:30 to 9:00 is for technicians to do a routine check on facilities and to update status of equipment.
    2. No student is allowed in the cleanroom after normal working hours.
  2. Working in the cleanroom is only authorized for members having a valid 'Authorization to work in MML 1 with clean room access'. This authorization is obtained after registration and approval from the director, when the requester has passed the Safety Test and his advisor has acknowledged to take responsibility for damage to equipment due to misconduct or by ignoring the present rules. The advisor taking responsibility for damage can only be a MML 1 member with an existing source of funding to pay for the usage fees and the eventual damage.
  3. Undergraduate Student wanting to work in the cleanroom additionally require to have a Clean-room mentor.
    The clean-room mentor is a MML 1 member who has been trained in the cleanrom since more than 6 months (but not another Undergraduate Student) and who normally shares the same advisor as the Undergraduate student.
    The cleanroom mentor can not be the mentor for more than 5 undergraduate students.
  4. No one is allowed to work alone in the cleanroom, there should always be at least two persons in the cleanroom at all time.
  5. In the cleanroom use proper safety attire or equipment as you have been trained and report any accidents immediately to the safety officer or technicians.
  6. Users must be certified before they can operate a machine alone.
    Certification can only be obtained by having a valid Certificate for Use of MML 1 Machine, endorsed by the Certifying MML 1 Member and the MML 1 Professor in Charge, after proper training.
    Training can be given by any user certified on the machine for more than 6 months.
    If any user is found using a machine without a valid Certificate, he will be banned from the clean-room for 4 months.
  7. Some machine can not be operated by all class of users (see the list), in this case the user can ask for the process to be performed by MML 1 staff using the form for Request for MML 1 Process.
    The reason for limiting the access to sensitive equipment is to avoid repetitive breakdown. The basic principle behind the separation in class is that the user having the most time to devote to training are allowed to use the most sensitive equipment. The rule for forbiding some equipment to undergraduate is security - no harmful gases or chemicals.
  8. Machines users must always book the machine before they use it, even if it is for the same day and up to 1 week in advance. At this time, they should verify the status of the machine.
    Failure to turn up half hour later will void the booking, but before another user can use the equipment he should ask the technician in charge who will change the booking.
  9. Heavily loaded equipment (mask aligner, SEM...) can not be booked in advance more than 4 hours per week by the same user.
    Note that same day 'booking' does not have any limitation and can exceed the 4 hours per week limit (to clarify: if you already have booked 4 hours for the coming week but nobody has booked the equipment for a particular slot today, then you just click on the slot and it is yours - no limitation!).
  10. If any user is found using a machine without booking, after a first verbal warning, his booking password will be supressed and he will have to go through the certification procedure again.
  11. All users of equipment must fill up the equipment log book and record all process runs and results, any machine abnormalities and defects in process quality.
    The record are used to help other users and help avoid repeating erroneous operation.
  12. Please report to the technicians immediately during working hours if the machine is discovered to behave abnormally or is damaged. Do not take corrective actions on the machine by yourself.
  13. Chemicals that are readily available for staff and students to use are AZ EBR Solvent,AZ Promoter(HMDS),AZ 9260 Photoresist,AZ 7220 Photoresist,AZ 400k Developer and AZ 300k Developer.
  14. Standard Chemicals use in wet bench
    Solvent-
    1.Acetone CMOS 4LT/BOT (CH3)2CO
    2.Propanol CMOS 4LT/BOT ((CH3)2 CHOH)

    Acid-
    1.Buffered Oxide Etch 7:1 VLSI
    2.Sulphuric Acid 96% VLSI

    Alkali-
    1.Potassium Hydroxide(KOH)-solid E/G 85%

    Etchant-
    1.Aluminum Etchant 16-1-1-2 CMOS
    2.Gold Etchant-Potassium Iodide/Iodene sublimed Bar
    3.Copper Etchant

    Redox Reagent-Oxidizer
    1.Hydrogent Peroxide
  15. Other Chemicals found in Store
    Solvent-
    1.Ethanol Abxolute (C2H6)
    2.Methanol (CH3OH)

    Hazardous-
    1.Ammonium Fluoride (NH4F)
    2.Ammonium Hydroxide(NH4OH)
    3.Hydrochloric (HCL)37%FINYTE (HCI)
    4.Hydrofluoric ACID 49% VLSI (HF)
    5.Nitric (HNO3) 70% FINYTE (HNO3)
    6.TMAH 25% FINYTE Grade 1 (CH3)4NOH
    7.Everplate Cu200 Base Plating solution
    8.Everplate Cu200 Brightener
    9.Everplate Cu200 Leveller B11
  16. Chemicals that are allowed to be use in cleanroom and DO NOT REQUIRED CENTRE APPROVAL are Nano GBL Thinner, Nano Removar PG, SU8 Series Resist,SU8 2000 Series Resist, SU8 Developer,Omni Coat, XP SU8 R50 Resin, Sylgard 184 Silicon Elastomer Kit (Base) and Sylgard 184 Silicon Elastomer Curing Agent.
  17. All damaged machine during after-hour must be reported to the TIC with a note on the technician desk.
  18. It is now mandatory for cleanroom users to wear goggle inside the cleanroom. These can now be located at the entrance to the cleanroom along side the rest of the cleanroom attire.

This webpage has been updated on Thursday, October 08, 2009.