Identification method for an article using crystal defects

• US 6,760,472 B1
• Filed: 12/10/1999
• Issued: 07/06/2004
• Est. Priority Date: 12/14/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ninomiya, Takanori, Takeda, Kazuo, Sugimoto, Aritoshi
• Primary Examiner(s): Wu, Jingge
• Assistant Examiner(s): Hesseltine, Ryan J.
• Application Number:
  US09/457,741
• Time in Patent Office: 1,670 Days
• Field of Search: 438/16, 438/401, 235/380, 235/382, 235/454, 235/460, 382/108, 382/145, 382/149, 382/115, 902/4, 902/25, 902/26, 902/27, 902/28, 902/29
• US Class Current: 382/149
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 19/073 Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14
• CPC Class Codes: G06K 19/07372 by detecting tampering with the circuit
• CPC Class Codes: G06K 19/14 the marking being sensed by radiation
• CPC Class Codes: G06K 7/10544 by scanning of the records by radiation in the optical part of the electromagnetic spectrum
• CPC Class Codes: H01L 2223/54413 comprising digital information, e.g. bar codes, data matrix
• CPC Class Codes: H01L 2223/5444 for electrical read out
• CPC Class Codes: H01L 2223/5448 Located on chip prior to dicing and remaining on chip after dicing
• CPC Class Codes: H01L 2223/54493 Peripheral marks on wafers, e.g. orientation flats, notches, lot number
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/544 Marks applied to semiconductor devices or parts, e.g. registration marks, alignment structures, wafer maps test patterns for characterising or monitoring manufacturing processes H01L22/00
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/207 : Diameter ranges

Abstract

A semiconductor substrate has a peculiar crystal defect. Crystal defects in a fixed area of a substrate can be treated as data acquired by coding the distribution of the crystal defects. The coded data is utilized for certificate data of an IC card by identifying a semiconductor substrate itself.

Claims

1. A method for identifying an article including the steps of:

mounting a semiconductor chip on a surface of said article;

irradiating a plurality of light of various wavelengths on a fixed area of said semiconductor chip;

measuring crystal defects, which have occurred in said semiconductor chip in a semiconductor material production process, in said fixed area of said semiconductor chip;

recording the pattern of measured positions of said crystal defects as an ID code of said article;

measuring crystal defects in a fixed area of a semiconductor chip mounted on an objective article to be identified;

transferring the pattern of measured positions of said crystal defects of said semiconductor chip mounted on said objective article to an ID code;

comparing said ID code with ID codes recorded; and

determining that said objective article corresponds to an article which has the same ID code recorded, on condition that said ID code is the same ID code with a recorded ID code.

2. A method for identifying an article according to claim 1,

wherein, said ID code is determined according to positions of crystal defects shown on two-dimensional coordinates representing a range divided at a fixed interval in X and Y directions of said fixed area of said semiconductor chip.

3. A method for identifying an article according to claim 2,

wherein, said range is represented by a specified mark on the surface of said semiconductor chip.

4. A method for identifying an article according to claim 2,

wherein, said range is specified by at least one cutout or projection made on one surface of said semiconductor chip.

5. A method for identifying an article according to claim 1,

wherein, said semiconductor chip is made of silicon on an insulator (SOI).

6. A method for identifying an article according to claim 2,

wherein, said range is specified by at least one cutout or projection made on one surface of covering material of said semiconductor chip.

7. A method for identifying an article, including the steps of:

mounting a semiconductor chip, in which plural numbers of memory cells are formed, on a surface of said article;

detecting a fail bit pattern of memory cells in a fixed address space of said semiconductor chip;

recording the fail bit pattern of said memory cells as an ID code of said article;

detecting a fail bit pattern of memory cells in a fixed address space of a semiconductor chip mounted on an objective article to be identified;

transferring the fail bit pattern of said memory cells of said semiconductor chip mounted on said objective article to be identified to an ID code;

comparing said ID code with ID codes recorded; and

determining that said objective article corresponds to an article which has the same ID code recorded, on condition that said ID code is the same ID code with a recorded ID code.

8. A method for identifying an article according to claim 7,

mounting a semiconductor chip, in which plural numbers of memory cells are formed, on a surface of said article;

wherein said fail bit pattern shows good or bad bit results and records the results together with an address, and a method of multivaluing the analog electric characteristic of a device corresponding to one address and recording the one address is enabled.