This Application Note describes a new quantitative method for the determination of ultratrace elemental impurities present in photovoltaic grade silicon using the Agilent 7500cs ICP-MS. Boron (volatile element) and phosphorus (subject to Si-based interferences) are of particular importance to the industry; therefore, special attention was given to the sample pretreatment stage in order to analyze these elements by ICP-MS. Good recov- ery results for all elements validated the sample preparation strategy. Example data for a range of elements present in 13 different Si samples is presented, along with a list of detection limits. B and P can be determined at the low ppb level in the solid and other elements studied can be measured at the ppt level.
The document details a new quantitative method for analyzing ultratrace elemental impurities in photovoltaic grade silicon using the Agilent 7500cs inductively coupled plasma mass spectrometer (ICP-MS). It addresses specific analytical challenges, particularly the determination of boron and phosphorus, which are critical for solar device efficiency but difficult to analyze due to volatility and matrix interferences.
| Instrument Model | Agilent 7500cs ICP-MS |
|---|---|
| Nebulizer | Agilent Micro Flow 100 |
| Spray Chamber | inert PFA with sapphire torch injector |
| Autosampler | Agilent Integrated Autosampler (I-AS) |
| RF Power | 1600 W |
| Carrier Gas Flow | 0.8 L/min |
| Analysis Time | 9 min per sample |
Boron and phosphorus are of particular importance to the industry for solar silicon analysis.
Phosphorus is determined by measuring the PO polyatomic ion at mass 47 using cool plasma conditions.
Boron and phosphorus can be determined at the low ppb level in the solid.