Tier-1 Semiconductor Hwaseong NRD Line ZEISS AIMS 1x DVIA-P4000 (220804R2) Inspection Report

Compared with the previous visit tuning, vibration levels had worsened.

Inspection was performed with the ZEISS equipment turned off to verify that the vibration isolation platform operates and performs normally.

Model: DVIA-P4000

Serial Number: 190724R2(220804R2)

Youngha Lee from DAEIL SYSTEMS

November 16, 2023

Tier-1 Semiconductor NRD Line 3F, Hwaseong

Tier-1 Semiconductor

AIMS 1x

November 20, 2023

17.12.27~17.12.29

For all six axes, arbitrary vibration is applied to the top plate through actuators and an open loop is configured; the accelerometer output for the excitation is plotted to control top-plate vibration through feedback gain.

Open-Loop Test confirms normal operation of the servo valve passive state and actuator output.

At the phase crossover, −5 dB or below; at the zero crossing, (X, Y, Z axes: 130–140 Degrees; rotational axes P, R, W: 130 Degrees or below) isolator stability is secured.

Z-axis open-loop tuning shows −9.33 dB at the phase crossover and 130–140 Degrees at the zero crossing — an appropriate graph shape.

Z-axis (1Z, 2Z, 3Z, 4Z) servo valves and Z1, Z3 accelerometers confirmed normal operation.

P-axis open-loop tuning shows −9.53 dB at the phase crossover and 130 Degrees or below at the zero crossing — an appropriate graph shape.

Z-axis (1Z, 2Z, 3Z, 4Z) servo valves and Z1, Z2 accelerometers confirmed normal operation.

R-axis open-loop tuning shows −9.83 dB at the phase crossover and 130 Degrees or below at the zero crossing — an appropriate graph shape.

Z-axis (1Z, 2Z, 3Z, 4Z) servo valves and Z2, Z3 accelerometers confirmed normal operation.

X-axis open-loop tuning shows −5.41 dB at the phase crossover and 130–140 Degrees at the zero crossing — an appropriate graph shape.

X-axis (2X, 4X) servo valves and X2 accelerometer confirmed normal operation.

Y-axis open-loop tuning shows −6.66 dB at the phase crossover and 130–140 Degrees at the zero crossing — an appropriate graph shape.

Y-axis (1Y, 3Y) servo valves and Y1, Y3 accelerometers confirmed normal operation.

W-axis open-loop tuning shows −8.12 dB at the phase crossover and 130 Degrees or below at the zero crossing — an appropriate graph shape.

X-axis (1Y, 3Y) servo valves and Y1, Y3 accelerometers confirmed normal operation.

All DVIA-P4000 servo valves and accelerometers were confirmed to operate normally.

A resonance-shaped graph not seen in open-loop appears at 0–10 Hz.

This is suspected to be due to external vibration sources or vibration sources on the top plate rather than a structural issue.

Transmissibility at or below 0 dB from 0–20 Hz confirms normal isolation operation.

Transmissibility at or below 0 dB from 0–20 Hz confirms normal isolation operation.

Feedback operation stability and performance verification complete.

A vibration source on the top plate in the Z-axis low-frequency band or a connecting path transmitting surrounding vibration is suspected.

Low-frequency (0–10 Hz) isolation performance is not good.

When floor vibration is applied, the transmissibility graph shape appears correctly.

Floor vibration is being isolated correctly.

Transmissibility at 3–7 Hz is slightly insufficient but within the normal performance range.

Transmissibility is within the normal performance range.

Z Axis, X Axis analysis: as noted in the Feedback Transmissibility graph, external vibration transmitted to the top plate or a top-plate vibration source is highly likely.

Equipment Turn off state

Floor vibration at 1–10 Hz is very low (VC-G or below), but top-plate vibration rises to about VC-E.

From 20 Hz onward, top-plate vibration is smaller than floor vibration.

To check whether Access Floor influences this vibration, excitation positions 1 and 2 were tested as shown below.

Lower-sensor vibration rises to VC-D and VC-C under excitation influence, while upper-sensor vibration remains unchanged compared with no excitation and stays at VC-E.

Lower-sensor vibration is at a similar level to excitation 1, confirming similar excitation.

Upper-sensor vibration increased to VC-C in the 1–20 Hz band.

Lower-sensor vibration is VC-C; upper-sensor vibration is VC-E — all frequency bands are clearly isolated.

Lower-sensor vibration is VC-D; upper-sensor vibration is VC-E — all frequency bands are clearly isolated.

Equipment Turn on state

Lower-sensor vibration is unchanged, but vibration at 10–40 Hz increases significantly.

Vibration at these frequencies occurs when the equipment is Turn on.

Lower-sensor vibration is unchanged, but vibration at 10–40 Hz increases significantly.

Vibration at these frequencies occurs when the equipment is Turn on.

Lower-sensor vibration is unchanged, but vibration at 10–40 Hz increases significantly.

Vibration at these frequencies occurs when the equipment is Turn on.

Upper-sensor vibration levels during Z-axis measurement varied depending on excitation position.

When excitation was applied near the sub-utility and controller Access Floor, top-plate sensor vibration increased — vibration may flow in through connections between equipment.

Installing isolators on the sub-utility and controller sections may offer mitigation.

Z, X, and Y axes all reach VC-C due to equipment Turn on vibration at 10–40 Hz.

Excluding that band, VC-E is satisfied.

2022.09.16 final 3rd setup VC-Curves and Transmissibility graph

As of September 2022, Z and X axes satisfied VC-E (Y axis only VC-D in the ~50 Hz band).

Transmissibility graphs show no major change from that time, so isolator operation is judged unchanged.

Changes to ZEISS equipment utilities or structure after September 2022, or Tier-1 Semiconductor utility or surrounding environment changes, are suspected as the cause.

Open-Loop Test and Feedback Transmissibility graph review suggest a vibration source on the top plate in the Z-axis low-frequency band or a connecting path transmitting surrounding vibration.

When excitation was applied near the sub-utility and controller Access Floor, top-plate sensor vibration increased — vibration may flow in through connections between equipment.

Installing isolators on the sub-utility and controller sections may offer mitigation.

Z, X, and Y axes all reach VC-C due to equipment Turn on vibration at 10–40 Hz.

Results as of September 2022 satisfied VC-E (Y axis peak VC-D); changes after September 2022 to ZEISS equipment utilities or structure, or Tier-1 Semiconductor utility or surrounding environment, are suspected as the cause.