Automated Wafer Insulation Resistance Test Solution

In the Back-End-of-Line (BEOL) stage of semiconductor manufacturing and wafer pre-shipment (CP) testing, insulation layer quality directly determines chip yield and long-term reliability. After multi-layer metal routing and passivation treatment (such as PSG, BPSG), complex capacitance and resistance structures form between metal layers and between metal layers and the silicon substrate.

1. Test Requirements

1. Interlayer Insulation Evaluation

Detect the insulation resistance between adjacent metal routing layers and screen micro-shorts caused by incomplete etching or particle contamination.

2. Passivation Layer Withstand Voltage and Leakage Current Testing

Evaluate the integrity of the wafer surface passivation layer and measure its leakage current and insulation resistance under specific bias to prevent potential breakdown risks.

3. High-Speed Testing

Wafer testing faces enormous capacity pressure, and traditional single-channel testing cannot meet throughput requirements, so equipment supporting high-speed testing is needed.

2. Equipment Selection and Configuration (Customer Case)

High Voltage and High Precision

The AT683 supports any output voltage from 1V~1000VDC with an insulation resistance measurement range up to 100kΩ~10TΩ, which is essential for simulating insulation layer stress tests at different operating voltages.

High-Speed Test Capability

The instrument offers ultra-fast testing of up to 55 tests per second and supports automatic or manual switching of four ranges, meeting the strict takt time requirements of semiconductor automated production lines.

Automation Interfaces

A built-in RS-232C interface compatible with the SCPI standard command set facilitates remote centralized control, data acquisition and real-time analysis from a host computer (PC).

Smart Sorting

The instrument provides comparator (sorting) functions with 30 built-in record sets, directly judging the DUT as GD/NG (good/no good) and outputting results via buzzer or interface; all test data (including timestamps, test voltage, insulation resistance values and judgement results) is uploaded to the database in real time for subsequent SPC (statistical process control) analysis and quality traceability.

3. Summary of Core Advantages

High Efficiency and High Throughput

Multiple instruments working with a multi-station turntable enable batch processing of wafer insulation testing, significantly reducing the cost per die tested.

High Sensitivity and Accuracy

Relying on the measurement capability of the AT683, tiny defects in the insulation layer can be captured accurately to intercept potentially failing products in advance.

High Safety and Interference Immunity

It effectively reduces electromagnetic crosstalk and surface leakage current interference in high-voltage test environments, ensuring test data is truthful and reliable.