EP0249762A1
Expired / Lapsed
EP
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Identifying semiconductor wafers with bar code patterns thereon
Assignee: Fujitsu Ltd
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Filing: 1987-05-20
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Granted: —
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Expires: 2007-05-20
Abstract
Abstract In automatic wafer processing for manufacturing gate array integrated circuits, it is necessary to identify each wafer (1) at the beginning of each process step. This is achieved by detecting a bar code pattern (5) provided on the wafer (1). A light source (20) which abundantly provides infrared light is positioned at the back side of the wafer (1) and a detector (24) at the front side thereof. The infrared light from the light source (20) easily penetrates the silicon wafer (1) and is received at the detector without any significant effect of reflection due to deposited layers on the front side of the wafer. The bar code pattern (5) is such as to selectively modify (e.g. selectively block) transmission of infrared light. A first metallization layer (Al-I) is a very suitable layer for use to form a bar code pattern, which can be easily formed in the layer by a laser beam scriber.
Inventors
- 👤 Tadashi Fujitsu Ltd. Patent Dept. Kiriseko
- 👤 Nobuo Fujitsu Ltd. Patent Dept. Iijima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 22:48
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/12; H10P90/128; H10W; H10W46/00; H10P72/00; H10P72/06; H10P72/0614; H10P72/0618; H10W46/401; H10W46/501; Y; Y10; Y10S; Y10S235/00; Y10S235/901
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
56 words
A method for identifying a semiconductor wafer utilizing a bar code pattern formed thereon, said method comprising: applying light including infrared light to a first side of the semiconductor wafer; receiving infrared light transmitted through said semiconductor wafer, at a second side of said semiconductor wafer; and identifying the semiconductor wafer by decoding the received light.
Claim 2
Independent Claim
56 words
A method for identifying a semiconductor wafer utilizing a bar code pattern formed thereon, said method comprising: applying light including infrared light to a first side of the semiconductor wafer; receiving infrared light transmitted through said semiconductor wafer, at a second side of said semiconductor wafer; and identifying the semiconductor wafer by decoding the received light.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1, wherein the infrared light is applied to the back side of the semiconductor wafer and the transmitted infrared light is received at the front side thereof.
Claim 4
Dependent Claim
33 words
A method as claimed in claim 1, wherein the infrared light is applied to the front side of the semiconductor wafer and the transmitted infrared light is received at the back side thereof.
Claim 5
Dependent Claim
29 words
A method as claimed in claim 1, 2 or 3, wherein the bar code pattern is formed utilising a metal layer having a low transmission factor for infrared light.
Claim 6
Dependent Claim
14 words
A method as claimed in claim 4, wherein the metal layer is of aluminum.
Claim 7
Dependent Claim
27 words
A method as claimed in claim 4 or 5, wherein the bar code pattern is formed by scribing and evaporating the metal layer with a laser beam.
Claim 8
Independent Claim
27 words
A method as claimed in any preceding claim, wherein the bar code pattern is formed utilising a metal layer which is deposited as a first metallization layer.
Claim 9
Dependent Claim
38 words
A method as claimed in claim 7, wherein a window or windows is or are formed above said bar code pattern area with regard to the or each subsequently formed metal layer in the case of multilevel metallization.
Claim 10
Dependent Claim
55 words
A method as claimed in claim 1, 2 or 3, wherein said bar code pattern is formed on the semiconductor wafer by scribing a surface thereof with a laser beam, and a window or windows is or are formed above said bar code pattern area with regard to the or each subsequently formed metal layer.
Claim 11
Independent Claim
153 words
A method for manufacturing a semiconductor device comprising: performing bulk processes comprising at least impurity introduction into a semiconductor wafer and forming an insulating layer thereon; forming a metal layer capable of blocking transmission of infrared light on said semiconductor wafer in respect of a first region, wherein an electrical element is to be formed, and in respect of second region wherein a bar code pattern is to be formed; removing selectively said metal layer in said second region, to form said bar code pattern; applying infrared light to the second region from a first side of said semiconductor wafer and detecting at a second side of the wafer infrared light transmitted through said semiconductor wafer and the bar code pattern and decoding said bar code pattern; identifying said semiconductor wafer by means of the decoding; and selectively removing said metal layer, whereby a specified metal pattern is formed corresponding to said identification.
Claim 12
Independent Claim
153 words
A method for manufacturing a semiconductor device comprising: performing bulk processes comprising at least impurity introduction into a semiconductor wafer and forming an insulating layer thereon; forming a metal layer capable of blocking transmission of infrared light on said semiconductor wafer in respect of a first region, wherein an electrical element is to be formed, and in respect of second region wherein a bar code pattern is to be formed; removing selectively said metal layer in said second region, to form said bar code pattern; applying infrared light to the second region from a first side of said semiconductor wafer and detecting at a second side of the wafer infrared light transmitted through said semiconductor wafer and the bar code pattern and decoding said bar code pattern; identifying said semiconductor wafer by means of the decoding; and selectively removing said metal layer, whereby a specified metal pattern is formed corresponding to said identification.
Claim 13
Dependent Claim
138 words
A method as claimed in claim 10, further comprising: forming an insulating layer capable of transmitting infrared light on said metal layer forming a specified pattern in the first region and on said bar code pattern in the second region; forming an additional second metal layer on an entire surface of said insulating layer; removing said additional second metal layer above the second region; applying infrared light to the second region from a first side of said semiconductor wafer and detecting at a second side of the wafer infrared light transmitted through said semiconductor wafer and the bar code pattern and decoding said bar code; identifying said semiconductor wafer by means of the decoding; and selectively removing said additional second metal layer, whereby a specified pattern of the additional second metal layer is formed corresponding to said identification.
Claim 14
Independent Claim
40 words
A method as claimed in 10 or 11, wherein a gate structure for a gate array is formed in said first region and said metal layer having a specified pattern is connected to said electrical element in the first region.
Claim 15
Dependent Claim
40 words
A method for manufacturing a semiconductor, as claimed in claim 11, or claim 12 when read as appended to claim 11, wherein said additional second metal layer having a specified pattern is connected to said metal layer of claim 10.
References Cited (Backward Citations)
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