Common faults and solutions of vacuum coating CVD electric furnace

The common faults and solutions of vacuum coating CVD electric furnace are as follows:

1. Vacuum system malfunction
Insufficient vacuum degree or inability to reach the set value
Possible reasons: vacuum pump malfunction, vacuum pipeline leakage, aging or damaged seals, vacuum gauge malfunction, etc.
resolvent:
Check if the vacuum pump is working properly, and repair or replace it promptly if there is a malfunction.
Use a helium mass spectrometer leak detector to locate the leak point and repair the leaking area.
Replace aging or damaged seals, such as O-ring seals.
Calibrate or replace the vacuum gauge to ensure accurate readings.
Sudden decrease in vacuum degree
Possible reasons: damage to the sealing ring of the evaporation source water circuit, perforation of the crucible, breakdown of the high-voltage electrode seal, and damage to the sealing ring of the working rotation seal.
resolvent:
Replace damaged rubber rings or seals.
Replace the crucible that has been pierced.
Check and repair the sealing of the high-voltage electrode.
Vacuum extraction time is too long
Possible reasons: excessive dust in the evaporation chamber, contamination or aging of the diffusion pump oil, excessive back pressure in the front stage pump, damage to the dynamic sealing rubber rings, etc.
resolvent:
Clean the evaporation chamber and remove dust.
Clean the diffusion pump and replace it with new oil.
Clean or replace the front stage pump to reduce the back pressure.
Replace the damaged dynamic sealing gasket.

2. Heating system malfunction
Abnormal temperature (too high or too low)
Possible reasons: incorrect temperature controller parameter settings, solid-state relay faults, damaged heating elements, circuit blockages, etc.
resolvent:
Check and calibrate the temperature controller parameters to ensure they are consistent with the set values.
Use a multimeter to check if the output terminal of the solid-state relay is broken down, and replace it promptly if it is damaged.
Check if the heating element is damaged, and replace it promptly if it is damaged.
Check if the circuit connections are unobstructed and repair any open or short circuits.
Heating element not working
Possible reasons: power failure, heating element open circuit, temperature controller failure, etc.
resolvent:
Check if the power supply is functioning properly.
Use a multimeter to check if the heating element is open circuited, and replace it promptly if there is an open circuit.
Check if the thermostat is working properly, and repair or replace it promptly if there is a malfunction.

3. Gas supply system malfunction
Unstable gas flow rate
Possible reasons: gas pipeline leakage, gas pressure reducing valve malfunction, gas flow meter malfunction, etc.
resolvent:
Check if the gas pipeline connection is tight and repair the leaking area.
Check if the gas pressure reducing valve is working properly, and repair or replace it promptly if there is a malfunction.
Calibrate or replace the gas flow meter to ensure accurate readings.
Insufficient purity of process gas
Possible reasons: contamination of the gas supply system, excessive impurities in the gas cylinder, etc.
resolvent:
Clean the gas supply system and remove impurities.
Replace the gas cylinder with a higher purity.

4. Other faults
Excessive vibration or abnormal operating sound of the equipment
Possible reasons: unstable contact between the machine base and the ground, loose anchor bolts, poor alignment, high heat generation in the bearing area, etc.
resolvent:
Adjust the contact between the machine base and the ground to ensure stability.
Tighten the anchor bolts to prevent loosening.
Re center and lock the equipment.
Check the bearing parts, improve lubrication conditions or replace the bearings.
Difficulty starting equipment or motor tripping
Possible reasons: internal freezing or rusting of the pump, improper adjustment of current protection in the distribution panel, motor failure, etc.
resolvent:
Use steam heating to melt ice or apply force to the rotor to remove rust.
Adjust the thermal relay to its rated value to ensure proper current protection.
Check if the motor is working properly, and repair or replace it promptly if there is a malfunction.