Monitoring vs. Controlling
The quartz crystal microbalance (QCM) monitor displays the deposition rate and total thickness of a depositing thin film but has no outputs or feedback to control the power applied to the deposition source during the deposition. However, some monitors have set-point relays that allow a particular deposition to be stopped when the predetermined film thickness is reached.
The QCM controller also displays the deposition rate and total thickness but by contrast provides instantaneous feedback about the deposition rate to the deposition source's power supply. That is, during the process, any variation in the deposition rate can be corrected by automatic adjustments to the power supply. Most controllers have internal PID logic that allows the operator to adapt the control characteristics to suit most deposition sources available.
Film Thickness Monitor or Controller Components:
To simplify the ordering process, the following components are required to make up a complete package:
- Sensor: Holds the crystal in a position where it will be exposed to the material being deposited.
- Crystal (gold, silver, or alloy, based on application): Determines oscillator frequency which changes as the crystal becomes coated.
- Optional Sensor Shutter: Air-actuated cover exposes or shields the crystal from the material being deposited. Required for dual sensors. Appropriate feedthrough and shutter control valve needed.
- In-Vacuum Cable: Coaxial cable connects the sensor to the feedthrough. (Not required for Cool Drawer sensors and Front Load Bakeable Sensors)
- Feedthrough: Carries electrical signals, cooling water, and/or air through the vacuum chamber wall.
- 6-inch BNC Cable: Coaxial BNC cable connects feedthrough to oscillator.
- Oscillator*: The electronics that operate the crystal.
- Sensor Input Cable: Coaxial BNC or Multi-Conductor cable connects the oscillator to the input of the Monitor/Controller.
- Monitor/Controller: The electronics and software that operate the system.
A monitor measures deposition rate and thickness. A controller also provides an output signal to control source power supply and deposition rate.
* Oscillators are not interchangeable; they are tuned to a specific monitor or controller
Deposition Monitor & Controller Selection Guide
| FTM-2400-S & FTM-2400-H Monitors |
FTC-2800 & FTC-2800C Controller |
XTC/3M & XTC/3S Controllers |
IC/6 Controller |
Cygnus Controller |
|
|---|---|---|---|---|---|
| View Product | View Product | View XTC/3M View XTC/3S |
|||
| Measurement Frequency Range |
1.0 to 6.5 MHz | 1.0 to 6.5 MHz | 5.0 to 6.0 MHz | 4.5 to 6.0 MHz | 4.5 to 6.0 MHz |
| Measurement Resolution |
0.37 Å(S); 0.037 Å(H) | ± 0.015 Å | ±0.034 Å | ±0.00433 Å | ±0.0042 Å |
| Reference Frequency Stability |
±2 ppm total (0 to 50°C) | ±2 ppm total (0 to 50°C) | ±2 ppm total (0 to 50°C) | ±2 ppm total (0 to 50°C) | ±2 ppm total (0 to 50°C) |
| Rate Display Resolution |
- | 0.01 Å/sec | 0.1 A/s for 0.0 to 99.9 A/s 1 A/s for 100 to 999 A/s |
0.001 for 0 to 9.999 Å/s 0.01 for 0 to 99.99 Å/s 0.1 for 100 to 999.9 Å/s |
0.001 for 0 to 9.999 Å/s 0.01 for 0 to 99.99 Å/s 0.1 for 100 to 999.9 Å/s |
| Frequency Rate Resolution |
±0.30 Hz(S); ± 0.03 Hz(H) | ±0.012 Hz | ±0.028 Hz @ 6 MHz | ±0.0035 Hz @ 6 MHz | ±0.0035 Hz @ 6 MHz |
| Measurement Interval |
0.10 to 2.0 s (adjustable) | 0.10 to 1.0 s (adjustable) | 0.25 s | 0.10 s | 0.10 s |
| Thickness Accuracy |
- | 0.50% | 0.50% | 0.50% | 0.50% |
| Multiple Sensor |
Yes (Up to 6 sources) |
Yes (Up to 4 sources) |
Yes (Up to 2 sources) |
Yes (Up to 8 sources) |
Yes (Up to 6 sources) |
| Measurement | Conventional Oscillation | Conventional Oscillation | ModeLock | ModeLock | ModeLock w/ Auto Z |
| Auto Z | No | No | No | Yes | Yes |
| Auto Tune |
No | No | No | Yes | No |
| Co-Deposition | No | Yes (Up to 4 sources) FTM-2800C only |
No | Yes (Up to 6 sources) |
Yes (Up to 6 sources) |
| Film Programs |
99 | 50 | 9 (XTC/3S); 32 (XTC/3M) | 32 | - |
| Processes | No | 100 | 1 (XTC/3S); 99 (XTC/3M) | 50 | - |
| Process Layers |
No | 1000 | 1 (XTC/3S); 999 (XTC/3M) | 200 | - |
| Data Logging |
Yes | Yes | Yes | Yes | Yes |
| On-Board Disk Drive |
No | No | No | Yes | Yes (Optional) |
| Single Sensors |
2 Standard 6 Optional |
2 Standard 4 Optional |
2 Standard | 2 Standard 8 Optional |
Up to 6 |
| Dual Sensors |
1 Standard | 1 Standard 2 Optional |
2 Standard (with XTL2 Optional) |
1 Standard 4 Optional |
6 (with on XTL2 per sensor input) |
| Crystal12™ Sensors |
No | Yes | Yes | Up to 8 | Up to 6 |
| Number of Sources |
No | 2 Standard 4 Optional |
2 Standard | Up to 6 | Up to 6 |
| Inputs | 4 Standard | 8 Standard, 16 Optional | 8 TTL | 14 Standard (Up to 28) | 14 Standard (Up to 28) |
| Outputs | 4 Standard | 8 Standard 16 Optional |
12 relays + 8 TTL | 8 Standard (Up to 24) programmable SPST relays. (14 Optional TTL available) |
8 Standard (Up to 24) programmable SPST relays. (14 Optional TTL available) |
| Communications Interface |
RS-232 Standard (TCP/IP or USB Optional) |
RS-232 and USB Standard (RS-232 and TCP/IP Optional) |
RS-232 Standard (TCP/IP and Ethernet Optional) |
RS-232 Standard Ethernet Optional |
RS-232 Standard (IEEE488 Optional) |
| Dimensions (H x W x D) |
3.5" x 8.5" x 7.75" 8.9 cm x 21.3 cm x 19.7 cm (half rack) |
5.23" x 8.4" x 10.0" 13.3 cm x 21.4 cm x 25.4 cm (half rack) |
3.5" x 8.0" x 12.0" 8.9 cm x 20.3 cm x 30.5 cm (half rack) |
5.25" x 19" x 13" 13.3 cm x 48.3 cm x 33.0 cm (full rack) |
5.25" x 19" x 13" 13.3 cm x 48.3 cm x 33 cm (full rack) |
Contact us by clicking here | +1 800 245 1656 for more information, including pricing and options, and to discuss your specific process application requirements.