Search

EP-4742882-A1 - ELECTRONIC CHIP COMPRISING A CRACK DETECTION DEVICE

EP4742882A1EP 4742882 A1EP4742882 A1EP 4742882A1EP-4742882-A1

Abstract

This description relates to an electronic chip comprising a crack detection device formed in and on a substrate or on the substrate, the device comprising a conductive path having an alternation of lower (201) and upper (203) conductive bands, the path comprising, for each lower band: a first (205A) and a second (205B) conductive vias in contact with the lower band, a third (207A) and a fourth (207B) conductive vias in contact with respectively one band and another upper band, at least a first (209A) and a second (209B) conductive tracks connecting respectively the first and third vias and the second and fourth vias, the first and second via being located directly above one and two ends of the lower band respectively, the third and fourth being located directly above one end of the band and the other upper band respectively.

Inventors

  • JOUAN, Gregoire

Assignees

  • STMicroelectronics International N.V.

Dates

Publication Date
20260513
Application Date
20251024

Claims (20)

  1. Crack detection device (216; 316) comprising an alternation of lower conductive bands (201, 201', 201'') and upper conductive bands (203, 203', 203'') connected in series, wherein the connection surfaces of the conductive bands to each other are entirely located within the 25% of the length of the conductive bands closest to the ends of the bands.
  2. Device (216; 316) according to claim 1, wherein the connection surfaces of the conductive strips to each other are entirely located within 20%, for example within 10% of the length of the conductive strips closest to the ends of the strips.
  3. Device (216; 316) according to claim 1 or 2, wherein at least 80% of the length of the device is occupied, in top view, by the upper conductive strips (203, 203', 203'') and at least 80% of the length of the device is occupied, in bottom view, by the lower conductive strips (201, 201', 201").
  4. Device (216; 316) according to any one of claims 1 to 3, wherein the lower conductive bands (201) are made of a doped semiconductor material and the upper conductive bands (203, 203', 203'') are made of metal.
  5. Device (216; 316) according to any one of claims 1 to 4, wherein the lower (201, 201', 201") and upper (203, 203', 203'') conductive strips define a conductive path between the first (118) and second (119) electrical connection terminals of the device.
  6. Device (216; 316) according to claim 4, wherein the conductive path comprises, for each lower conductive strip (201): - a first via conductor (205A) on and in contact with the lower conductive strip (201), - a second via conductor (205B) on and in contact with the lower conductive strip (201), - a third via conductor (207A) under and in contact with an overlying upper conductive strip (203), - a fourth conductor via (207B) below and in contact with another upper conductor strip (203') above, - at least one first intermediate conductive track (209A) connecting the first (205A) and third (207A) conductive vias, and - at least one second intermediate conductive track (209B) connecting the second (205B) and fourth (207B) conductive vias, the first via conductor (205A) being located in line with one end of the lower conductive strip (201) and the second via conductor (205B) being located in line with one end of the lower conductive strip (201), the third via conductor (207A) being located in line with one end of the upper conductive strip (203) above, and the fourth via conductor (207B) being located in line with one end of the other upper conductive strip (203') above.
  7. Device (216) according to claim 6, wherein: - the first via conductor (205A) is located directly above a central part of the upper conductive strip (203) above; - the second via conductor (205B) is located directly above a central portion of the other conductive strip superior (203') above; - the third via conductor (207A) is located directly above a central portion of the lower conductive strip (201); and - the fourth via conductor (207B) is located directly above said central part of the lower conductive strip (201).
  8. Device (216) according to claim 7, wherein, for each lower conductive strip (201), said central part of the lower conductive strip (201) occupies less than 50%, preferably less than 30%, and more preferably less than 20% of the length of said lower conductive strip (201).
  9. Device (316) according to claim 6, wherein the fourth via conductor (207B) is aligned with the second via conductor (205B), the fourth via conductor (207B) being located vertically above said second end of the lower conductive layer (201) and the second via conductor (205B) being located vertically above said end of the other upper conductive strip (203') above.
  10. Device (316) according to claim 9, wherein the third via conductor (207A) is located in line with an intermediate portion of the lower conductive strip (201) located in the vicinity of the second end of the lower conductive strip (201), said intermediate portion being located between a central portion and the second end of the lower conductive strip (201).
  11. Device (216; 316) according to any one of claims 6 to 9, wherein, for each lower conductive band (201), the first via (205A) is entirely located directly below the 25%, for example the 20%, for example the 10% of the length of the strip furthest from the second end of said lower conductive strip (201), and the second via (205B) is entirely located directly below the 25%, for example the 20%, for example the 10% of the length of the lower conductive strip (201) furthest from the first end of said lower conductive strip (201).
  12. Device (216; 316) according to any one of claims 1 to 11 wherein the lower conductive bands (201) are made of silicon.
  13. Device (216; 316) according to any one of claims 1 to 12, formed in and on a semiconductor substrate (101), in which the semiconductor substrate (101) comprises a portion (101P) doped with a first type of conductivity, the lower conductive bands (201) being entirely formed in said portion (101P) of the semiconductor substrate (101).
  14. Device (216; 316) according to any one of claims 1 to 13, wherein the lower conductive strips (201, 201', 201'') are separated two by two by insulation trenches (202).
  15. Device (216; 316) according to any one of claims 1 to 14 wherein each lower conductive band (201) is separated from a neighboring lower conductive band (201') by a distance of between 5 nm and 10 µm.
  16. Device (216; 316) according to any one of claims 1 to 15, wherein each upper conductive strip (203) is separated from a conductive strip superior (203') close to a distance between 20 nm and 10 µm.
  17. Electronic chip comprising at least one crack detection device (216; 316) according to any one of claims 1 to 16, the chip being delimited by an edge (110), the crack detection device (216; 316) being disposed between the edge (110) of the electronic chip (200) and an electronic circuit region (105) of the electronic chip.
  18. Chip according to claim 17, comprising several crack detection devices (216; 316) according to any one of claims 1 to 16.
  19. Method for manufacturing an electronic chip, comprising a step of forming a crack detection device (216; 316) according to any one of claims 1 to 16.
  20. Method of using an electronic chip according to claim 17 or 18, comprising a step of testing the electrical conductivity of the crack detection device.

Description

technical field This description relates generally to electronic chips, or integrated circuits, and in particular to an electronic chip comprising a crack detection device, for example integrated into a sealing ring, known as a "seal-ring" in English. Previous technique In industry, most electronic devices are manufactured in series. Several electronic chips are typically fabricated on the same semiconductor substrate, such as a single wafer or semiconductor slice. These chips can then be separated, or individualized, for use, for example, on their own or within an electronic device containing other components. This individualization is generally achieved by cutting, for example, with a saw. During this manufacturing process, for example when cutting a semiconductor wafer, a crack can form on the edge of an electronic chip and propagate through the chip. Such a crack can lead to failure of the electronic circuits within the chip. In addition, cracks can form during the lifetime of the chip, particularly on an edge of the chip, for example due to temperature changes in the electronic chip. To protect an electronic chip, particularly during manufacturing, individualization, or during In use, the electronic chip may include a sealing ring around its periphery. One purpose of the sealing ring is to prevent cracks from propagating from the edge to a region of the chip's electronic circuits. Another purpose of the sealing ring is to prevent moisture from penetrating the chip's active areas. However, the sealing ring does not always prevent crack formation and propagation within the electronic chip. Therefore, an electronic chip may include a crack detection device, for example, integrated into a sealing ring. The crack detection device can be used to test the chip's integrity during manufacturing, for example, after the dicing stage, or during the chip's use. It would be desirable to be able to improve, at least in part, electronic chips, and in particular the crack detection devices integrated into the electronic chips. Summary of the invention To this end, one embodiment provides an electronic chip comprising a semiconductor substrate and a crack detection device formed in and on the semiconductor substrate or on the semiconductor substrate, the crack detection device comprising, between the first and second electrical connection terminals of the device, a serpentine conductive path having an alternation of lower and upper conductive bands connected in series, wherein the conductive path comprises, for each lower conductive band: a first conductive via on and in contact with the lower conductive strip, a second via conductor on and in contact with the strip inferior conductivity, a third conductor via a conductor under and in contact with an overlying upper conductive strip, a fourth conductor via a conductor under and in contact with another, higher, overlying conductive strip, at least one first intermediate conductive track connecting the first and third conductive vias, and at least one second intermediate conductive track connecting the second and fourth conductive vias, the first via conductor being located directly above one end of the lower conductive strip and the second via conductor being located directly above one end of the lower conductive strip, the third via conductor being located directly above one end of the upper conductive strip above, and the fourth via conductor being located directly above one end of the other upper conductive strip above, at least 80% of the length of the crack detection device being occupied, in top view, by the upper conductive strips and at least 80% of the length of the crack detection device being occupied, in bottom view, by the lower conductive strips, and in which the lower conductive bands are made of a doped semiconductor material and the upper conductive bands are made of metal. According to one embodiment, in the crack detection device: the first via conductor is located directly above a central portion of the overlying upper conductive strip; the second via conductor is located directly above a central portion of the other overlying upper conductive strip; the third via conductor is located directly above a central part of the lower conductive strip; and the fourth via conductor is located directly above the said central part of the lower conductive strip. According to one embodiment, in the crack detection device, the fourth via conductor is aligned with the second via conductor, the fourth via conductor being located directly above said second end of the lower conductive layer and the second via conductor being located directly above said end of the other overlying upper conductive strip. According to one embodiment, in the detection device, the third via conductor is located directly above an intermediate portion of the lower conductive strip located in the vicinity of the second end of the lower conductive strip, said intermediate portion being locat