US4010355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor wafer having machine readable indicies
Assignee: Motorola Solutions Inc
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Filing: 1974-06-10
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Granted: 1977-03-01
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Expires: 1994-06-10
Abstract
Abstract Machine readable identifying indices for a semiconductor wafer having a top surface, a bottom surface, and at least one flat edge is placed on the bottom surface of the semiconductor wafer, positioned in a predetermined relationship to the flat edge, desirably parallel to the flat edge. Means is provided for directing a first beam of radiant energy at the machine readable code and a second beam of radiant energy at the semiconductor wafer proximate to the machine readable code. Sensing means detects the first and second beams after impinging on the semiconductor wafer. A differential amplifier produces a series of output pulses representing the machine readable code. The output from the sensing means constitutes the inputs to the differential amplifier. In a preferred form, the machine readable code is a bar code including error check symbols. This approach gives a simplified means for identifying semiconductor wafers that is highly reliable.
Inventors
- 👤 Kenneth Earl Roehrman
- 👤 Bernardus I. C. F. VAN Pul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:37
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/10861; H; H10; H10W; H10W46/00; H10W46/201
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
127 words
Means for identifying a semiconductor wafer having a top surface and a bottom surface comprising, in combination: a. a flat edge on said semiconductor wafer, b. a machine readable code and its complement positioned on the bottom of said semiconductor wafer in a predetermined relationship to said flat edge, c. means for directing a first beam of radiant energy at the machine readable code, d. means for directing a second beam of radiant energy at the complement of the machine readable code, e. means for sensing said first and second beams after impinging on said semiconductor wafer, and f. differential amplifier means for producing a series of output pulses representing said machine readable code, the outputs from said sensing means constituting the inputs to said differential amplifier.
Claim 2
Dependent Claim
127 words
Means for identifying a semiconductor wafer having a top surface and a bottom surface comprising, in combination: a. a flat edge on said semiconductor wafer, b. a machine readable code and its complement positioned on the bottom of said semiconductor wafer in a predetermined relationship to said flat edge, c. means for directing a first beam of radiant energy at the machine readable code, d. means for directing a second beam of radiant energy at the complement of the machine readable code, e. means for sensing said first and second beams after impinging on said semiconductor wafer, and f. differential amplifier means for producing a series of output pulses representing said machine readable code, the outputs from said sensing means constituting the inputs to said differential amplifier.
Claim 3
Dependent Claim
20 words
The means for identifying a semiconductor wafer of claim 1 in which said machine readable code comprises a bar code.
Claim 4
Dependent Claim
29 words
The means for identifying a semiconductor wafer of claim 2 in which said bar code comprises a row of symbols parallel to the flat edge of said semiconductor wafer.
Claim 5
Dependent Claim
46 words
The means for identifying a semiconductor wafer of claim 3 in which said bar code additionally comprises a second row of symbols, one of said rows of symbols representing an identifying number for said semiconductor wafer, and the other row of symbols representing an error code.
Claim 6
Dependent Claim
101 words
The means for identifying a semiconductor wafer of claim 4 in which said first and second beams are each directed at one of said rows of symbols, the symbols are binary members, the error code, in one of said rows of symbols, represents the complement of the identifying number in said other row of symbols, the one of said rows of symbols containing a binary 1 provides a data signal for a given position in said rows of symbols, and the other of said rows of symbols provides a reference signal for subtraction from said data signal by said differential amplifier.
Claim 7
Dependent Claim
28 words
The means for identifying a semiconductor wafer of claim 1 additionally comprising an integrating circuit connected between the output of said differential amplifier and said means for sensing.
Claim 8
Independent Claim
119 words
A method for identifying a semiconductor wafer which comprises: a. providing two rows of indicia constituting a machine readable code and its complement in a predetermined position on said semiconductor wafer, b. directing a first beam of radiant energy at one of the two rows of indicia, c. directing a second beam of radiant energy at the other of the two rows of indicia, d. sensing the first and second beams of radiant energy after impinging on the semiconductor wafer to produce signals representing indicia in the rows, and e. subtracting the signals resulting from one of the beams from the signals resulting from the other beam to produce a series of output pulses representing the machine readable code.
Claim 9
Independent Claim
119 words
A method for identifying a semiconductor wafer which comprises: a. providing two rows of indicia constituting a machine readable code and its complement in a predetermined position on said semiconductor wafer, b. directing a first beam of radiant energy at one of the two rows of indicia, c. directing a second beam of radiant energy at the other of the two rows of indicia, d. sensing the first and second beams of radiant energy after impinging on the semiconductor wafer to produce signals representing indicia in the rows, and e. subtracting the signals resulting from one of the beams from the signals resulting from the other beam to produce a series of output pulses representing the machine readable code.
Claim 10
Dependent Claim
73 words
The method of claim 7 in which the signal from the beam of radiant energy sensing the absence of an indicia at a given position in the rows is subtracted from the signal from the beam of radiant energy sensing the presence of an indicia at that given position in the rows, the polarity of the resulting signal serving to indicate which of the two rows contains the indicia at that given position.
Claim 11
Independent Claim
120 words
A method for identifying a semiconductor wafer having top and bottom surfaces which comprises: a. providing a machine readable code in a predetermined position on the bottom surface of said semiconductor wafer, b. directing first and second beams of radiant energy at the bottom surface of said semiconductor wafer to provide signals representing the machine readable code and a background after impinging on said semiconductor wafer, c. sensing the first and second beams of radiant energy after impinging on said semiconductor wafer to give a signal from each beam, and d. subtracting the signals resulting from one of the beams from the signals resulting from the other beam to produce a series of output pulses representing the machine readable code.
Claim 12
Independent Claim
120 words
A method for identifying a semiconductor wafer having top and bottom surfaces which comprises: a. providing a machine readable code in a predetermined position on the bottom surface of said semiconductor wafer, b. directing first and second beams of radiant energy at the bottom surface of said semiconductor wafer to provide signals representing the machine readable code and a background after impinging on said semiconductor wafer, c. sensing the first and second beams of radiant energy after impinging on said semiconductor wafer to give a signal from each beam, and d. subtracting the signals resulting from one of the beams from the signals resulting from the other beam to produce a series of output pulses representing the machine readable code.
Claim 13
Dependent Claim
49 words
The method of claim 9 in which the machine readable code comprises the identification of the wafer and the complement of the identification, the first beam of radiant energy being directed at the identification, and the second beam of radiant energy being directed at the complement of the identification.
Claim 14
Dependent Claim
92 words
The method of claim 10 in which the identification is provided as a first row of indicia, the complement is provided as a second row of indicia, and the signal from the beam of radiant energy sensing the absence of an indicia at a given position in the rows is subtracted from the beam of radiant energy sensing the presence of an indicia at that given position in the rows, the polarity of the resulting output pulses serving to indicate which of the two rows contains the indicia at that given position.
Claim 15
Dependent Claim
120 words
Apparatus for identifying a semiconductor wafer having a top surface and a bottom surface, which comprises: a. a machine readable code in a predetermined position on the bottom surface of said semiconductor wafer, b. means for directing a first and second beam of radiant energy at the bottom surface of said semiconductor wafer to provide signals representing the machine readable code and a background, c. means for sensing said first and second beams after impinging on said semiconductor wafer to give a signal from each beam, and d. differential amplifier means for producing a series of output pulses representing said machine readable code, the signals from each beam produced by said sensing means constituting the inputs to said differential amplifier.
Claim 16
Dependent Claim
120 words
Apparatus for identifying a semiconductor wafer having a top surface and a bottom surface, which comprises: a. a machine readable code in a predetermined position on the bottom surface of said semiconductor wafer, b. means for directing a first and second beam of radiant energy at the bottom surface of said semiconductor wafer to provide signals representing the machine readable code and a background, c. means for sensing said first and second beams after impinging on said semiconductor wafer to give a signal from each beam, and d. differential amplifier means for producing a series of output pulses representing said machine readable code, the signals from each beam produced by said sensing means constituting the inputs to said differential amplifier.
Claim 17
Dependent Claim
52 words
The apparatus of claim 12 in which said machine readable code comprises the identification of said wafer and the complement of the identification, the first beam of radiant energy is directed at the identification of said wafer, and the second beam of radiant energy is directed at the complement of the information.
Claim 18
Dependent Claim
61 words
The apparatus of claim 13 in which the identification of said wafer comprises a first row of indicia, the complement of the identification comprises a second row of indicia, the polarity of the output pulses from said differential amplifier serving to indicate which of said first and second rows of indicia contains an indicia at a given position in said rows.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-29 | 1980-08-30 | 1981-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-29 | 1984-08-30 | 1985-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-29 | 1988-08-30 | 1989-03-01 | $7700.00 | Window Closed / Lapsed |