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Silicon MEMS oscillators have superior reliability (operating life), robustness (ability to withstand shock and vibration) and resilience compared to quartz oscillators. SiTime has shipped more than 120 million units with zero MEMS field failures. MEMS resonators are made of silicon and manufactured in ultra-clean semiconductor foundries using proven design rules to ensure high yield and semiconductor-level quality. The qualification and life-time testing results lead to a mean time between failure (MTBF) of more than 500 million hours (FIT<2). Silicon MEMS devices demonstrate a shock and vibration resistance of 50,000 g and 70 g respectively.
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A comparison of MEMS oscillator and Quartz oscillator reliability and robustness is shown below.
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MEMS Oscillators
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Quartz Oscillators
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Reliability / MTBF
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500 million hours
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20-30 million hours
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Shock Resistance
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50,000 g shock
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5,000 g shock
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Vibration Resistance
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70 g vibration
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10 g vibration
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Built-in Quality
MEMS-based devices leverage a combination of high quality materials, sophisticated processes and well-established infrastructure. Purified monocrystalline silicon, the base material used for semiconductors and MEMS die, is fundamentally a pure, strong and stable material. MEMS resonators are etched in silicon wafers and encapsulated under a layer of poly-silicon that makes them extremely robust. MEMS resonator wafers are made in CMOS facilities using batch-manufacturing to produce devices with predictability and nanometer precision. Six sigma philosophy for process design and process control in combination with proven design rules ensures high quality. Learn more about how MEMS are manufactured.
The infrastructure that supports the manufacturing of quartz devices is much smaller. While silicon is reliable and robust, quartz crystals are fragile and devices manufactured with quartz material have inherent limitations. A key disadvantage of crystal oscillators is their susceptibility to vibration and the loss of stability with age. Vibration appears in the jitter performance of quartz devices. Silicon MEMS devices however, are not sensitive to vibration. MEMS devices resonate at a fundamental frequency in a mode that incident vibration does not modulate. Read more about the performance advantages of silicon.
SiTime’s MEMS oscillators pass all standard CMOS qualifications and additional resonator-specific tests (listed below) with zero failures.
| Test | Description |
| EFR | Early Life (125ºC 168 hrs dynamic) |
| HTOL | High Temperature Operating Life (125ºC 2000 hrs dynamic) |
| ESD | Electrostatic Discharge (HBM, MM, CDM) |
| LU | Latch Up (85ºC 150 mA) |
| HAST | Biased Temp and Humidity (85 hrs 130ºC 85% RH dynamic) |
| TC | Temp Cycle (MSL1 + 1000 cycles, -65ºC -150ºC) |
| QA | Quartz Style Aging (30 days 85ºC dynamic) |
| MS | Mechanical Shock (50kg shock multi-axis dynamic) |
| VFV | Variable Frequency Vibration (70g dynamic) |
| VF | Vibration Fatigue (20g 30 hrs dynamic) |
| CA | Constant Acceleration (30 kg dynamic) |
| HTS | High Temperature Storage (125ºC 1000 hrs) |
| PCT | Pressure Cooker Test (autoclave 120ºC 100% RH 2atm 96 hrs) |
| TS | Temp Shock (-55ºC -125ºC 100 cycles) |
| MSL1 | Moisture Sensitivity Level 1 (JEDEC) |
