5MHz Gold Electrode Crystals
Part No：AC5AD12
This 5MHz, 12mm gold-electrode quartz crystal offers excellent long-term frequency stability, combining a lower base frequency with a standard footprint. Gold electrodes provide low contact resistance, high chemical stability, and ease of deposition, making them ideal for monitoring low-stress materials such as gold, silver, and copper. However, due to the relatively high rigidity of the gold electrode, film stress may be transferred to the quartz substrate. For this 5MHz configuration, users should remain mindful of this stress transmission during long-term or thick-film deposition to prevent potential frequency jumps and ensure monitoring reliability.
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12mm-5MHz-Gold-Plated Precision Monitoring Crystal: Engineered for High-Durability Vacuum Coating Processes
The AC5AD12 is a 5MHz quartz crystal specifically designed for demanding vacuum coating applications requiring high mechanical robustness. Featuring a compact 12mm wafer diameter and a high-performance gold-plated electrode, this product utilizes the inherent chemical stability and ultra-low contact resistance of gold to ensure reliable monitoring for materials such as gold, silver, and copper. With its thicker quartz substrate compared to 6MHz models, the AC5AD12 offers superior durability and long-term stability, serving as a critical component for achieving consistent thickness monitoring in high-throughput production environments.
Process Advantages of Gold-Plated Electrodes
Superior Electrical Conductivity: The gold-plated electrode minimizes signal attenuation, ensuring precise data acquisition at the 5MHz resonant frequency—ideal for heavy-duty deposition processes that require stable, high-sensitivity feedback. Excellent Chemical Stability: As a noble metal coating, the gold electrode effectively resists oxidation and environmental corrosion, maintaining a stable resonance resistance (≤15Ω) even after multiple evaporation cycles, thereby preventing invalid frequency jumps. Optimized Stress Management: Through our proprietary electrode anchor design (2 anchors), the AC5AD12 optimizes stress transfer efficiency onto the quartz substrate, significantly mitigating film stress jitter during long-term monitoring and substantially enhancing the reliability of complex OLED and semiconductor coating processes.
Why Choose the 5MHz 12mm Series?
The 5MHz frequency configuration provides a thicker quartz base, achieving an ideal balance between mechanical strength and extended crystal lifespan, making it the preferred choice for high-reliability applications. Its 12mm diameter design ensures broad compatibility with mainstream single/dual sensor head monitors available on the market (such as standard Optorun models). Whether for heavy-duty semiconductor interconnect metallization, long-duration optical coating, or precision research growth monitoring, the AC5AD12 provides consistent, high-endurance monitoring performance from start to finish.
Product Specifications
| Part No | AC5AD12 |
| Nominal Frequency | 5.000MHz |
| Center Frequency | 4.995MHz |
| Frequency Tolerance | ±8KHz@25°C |
| Wafer Diameter | 12.42mm ± 0.03mm |
| Resonance Resistance | ≤15Ω |
| Crystal Cutting | AT-CUT |
| Electrode Material | Gold(Au) / Chrome(Cr) |
| Operating Temperature | 25°C ~ 75°C |
| Electrode Appearance | 2 anchors |
| Storage Temperature | -20°C ~ +85°C |
| Storage Humidity | RH 30~50% |
| Storage Life | Unlimited storage life |
applications of the quartz monitor crystal
Find answers to the most frequently asked questions .
Yes, the AC5AD12 is specifically engineered to be compatible with standard 12mm sensor heads widely used in Japanese vacuum coating systems, including those manufactured by Optorun, Shincron, and ULVAC
Gold electrodes offer superior chemical stability and lower contact resistance. They are particularly resistant to oxidation in complex vacuum environments, ensuring more reliable performance and a longer operational lifespan than silver electrodes in high-precision monitoring tasks.
The 5MHz crystal features a thicker quartz substrate, which provides higher mechanical strength and better durability during long-duration, high-thickness deposition processes. While 6MHz offers higher sensitivity for thinner films, 5MHz is favored in industrial applications where crystal longevity and robustness against stress are prioritized.
Gold electrodes provide exceptional chemical inertness, which is crucial for preventing oxidation during long-term monitoring cycles. Furthermore, their extremely low resistance ensures a high signal-to-noise ratio at the 5MHz resonant frequency, effectively minimizing frequency drift and measurement errors caused by electrode degradation.
Always wear anti-static gloves during handling to prevent contamination. Ensure the crystal is centered correctly within the 12mm sensor head housing. If frequency jumps occur, check for proper electrical contact and verify that the sensor head spring clips are not applying uneven pressure. If the deposited film reaches the maximum recommended thickness, the crystal should be replaced to maintain monitoring accuracy.
The AC5AD12 crystal features a highly stable design with an unlimited theoretical shelf life. However, for optimal performance, we recommend storage in a clean, dry environment with 30-50% RH. Keep the crystals in their original anti-static packaging until use to protect the electrode surface from airborne organic contaminants.
The AC5AD12 is designed for stable operation within 25°C to 75°C. In high-heat evaporation environments, we highly recommend the use of a water-cooled sensor head to manage radiant heat. Maintaining the crystal within its optimal temperature range is essential to prevent frequency distortion caused by thermal expansion of the quartz substrate.