UltraChip is an industrial ultrasonic C-scan dataset designed for chip-package defect inspection in non-destructive testing (NDT). All samples are collected from real-world environment, capturing practical challenges such as strong noise, subtle defect appearance, and process-dependent variations. The dataset is intended for research on unsupervised/weakly-supervised anomaly detection, defect localization, and robustness evaluation.

UltraChip is acquired using a high-precision scanning acoustic microscope system, where ultrasonic echoes are sampled and digitized to form C-scan grayscale images with fine structural details. The dataset contains approximately 8,000 ultrasonic images and covers three representative defect types: Hole, Crack, and Layer. For precise localization evaluation, every defective test image is provided with pixel-level ground-truth masks.

To reflect structural differences introduced by various packaging processes, UltraChip is further grouped into three structural categories: Bonding, Two-Lead, and Four-Lead, enabling benchmarking under diverse normal conditions and process-dependent appearance shifts.

Some sample images in UltraChip

The UltraChip dataset is organized in a hierarchical directory layout and is compatible with common unsupervised anomaly detection pipelines. Each category contains train/test/ground_truth splits.

• train/good/: normal-only training samples (Good).
• test/good/: normal test samples.
• test/hole/, test/crack/, test/layer/: defective test samples.
• ground_truth/: pixel-level masks for defective test samples (defect folders match defect types).

Tabel 1 summarize the number of samples in the training set (normal only) and the test set (good + defects) for each structural category:

Table 1: Detail Information of UltraChip

Category	Train (Good)	Test (Hole)	Test (Crack)	Test (Layer)	Test (Good)	Test Total	Total
Bonding	946	277	27	9	309	622	1,568
Four-Lead	2,787	394	5	1	405	805	3,592
Two-Lead	2,134	408	5	0	406	819	2,953
Overall	5,867	1,079	37	10	1,120	2,246	8,113

Recommended Directory Layout

UltraChip/
  Bonding/
    train/good/
    test/good/
    test/hole/
    test/crack/
    test/layer/
    ground_truth/hole/
    ground_truth/crack/
    ground_truth/layer/
  Four-Lead/
    ...
  Two-Lead/
    ...

We make UltraChip dataset available for academic research purposes. To access the dataset for research (noncommercial use), please send an email to luk@ucas.ac.cn with a signed AGREEMENT. Please note that any commercial use of the dataset is prohibited.