| 摘要 |
Through substrate vias (TSVs) are provided after substantially all high temperature operations needed to form a device region of a first thickness proximate the front surface of a substrate wafer by: (i) from the front surface, forming comparatively shallow vias of a first aspect ratio containing first conductors extending preferably through the first thickness but not through the initial wafer thickness, (ii) removing material from the rear surface to form a modified wafer of smaller final thickness with a new rear surface, and (iii) forming from the new rear surface, much deeper vias of second aspect ratios beneath the device region with second conductors therein contacting the first conductors, thereby providing front-to-back interconnections without substantially impacting wafer robustness during manufacturing and device region area. Both aspect ratios are desirably about ≦̸40, usefully ≦̸10 and preferably ≦̸5. |
