JP2005294531A - Semiconductor integrated circuit, manufacturing method thereof and mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit and the manufacturing method thereof capable of adding much amount of information and easily and surely confirming the history of manufacturing. <P>SOLUTION: An inherent mark for individual confirmation is marked on the manufacturing history indicating section 101 of a chip 202 formed on a wafer 201. The mark is obtained by erasing a part of some mark. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a semiconductor integrated circuit, a manufacturing method thereof, and a mask.

  IC (Integrated Circuit) has permeated every field, and it is important to improve the reliability of IC. The IC has been shipped after being packaged and packaged by an IC manufacturer, but has recently been shipped in a chip state. Chip ICs that are not packaged in this way are COG (Chip On Glass) that is directly mounted on a liquid crystal glass substrate, and COB (Chip) that is directly mounted on a substrate on which other components are mounted. On Board: Used for chip-on-board.

  When an IC is shipped in a packaged state, a manufacturing history such as a manufacturing date and a manufacturing place is recorded on the package. However, when an IC is shipped in a chip state, the manufacturing history must be recorded directly on the IC. However, since the IC is less susceptible to mechanical shock than the package, it is difficult to directly record the manufacturing history on the IC.

  Conventionally, a method for directly writing the manufacturing history on the IC is disclosed in, for example, Japanese Patent Laid-Open No. 3-64941 (Patent Document 1). According to Japanese Patent Application Laid-Open No. 3-64941, an IC pad is marked with a probe used in a prober test before the wafer is scribed and divided. In other words, in a state where a plurality of ICs are included in the wafer, the vacant pads of each IC are marked. The IC manufacturing history can be known by regarding the case where the mark is present as a binary number 1 and the case where the mark is not present as a binary number 0.

However, the method disclosed in Japanese Patent Laid-Open No. 3-64941 has a problem in that the amount of manufacturing history that can be provided to the IC is limited because the number of empty pads is limited. That is, there is a problem that a large amount of manufacturing history cannot be given to the IC.
Japanese Patent Laid-Open No. 3-64941

  Accordingly, an object of the present invention is to provide a semiconductor integrated circuit to which a large amount of manufacturing history and the like can be added and a method for manufacturing the same.

  Another object of the present invention is to provide a mask suitable for carrying out such a manufacturing method.

  In order to solve the above-described problem, the semiconductor integrated circuit according to the first aspect of the present invention is a semiconductor integrated circuit provided with a unique symbol for individual recognition, wherein the symbol is partly erased. It is said.

  According to the semiconductor integrated circuit having the above configuration, a part of a certain mark is erased from the unique symbol for individual recognition. Therefore, the shape of the symbol can be changed by changing the part to be erased. . Therefore, a plurality of symbols having different shapes can be obtained from one mark, and a large amount of manufacturing history can be added to the semiconductor integrated circuit.

  In the semiconductor integrated circuit of one embodiment, the symbol is a number.

  According to the semiconductor integrated circuit of the above embodiment, since the symbol is a number, the manufacturing history and the like can be easily and reliably recognized by looking at the symbol.

  In the semiconductor integrated circuit of one embodiment, the symbol is formed of a material that can be visually observed.

  According to the semiconductor integrated circuit of the above embodiment, since the symbol is formed of a material that can be visually observed, the manufacturing history and the like can be recognized more easily and reliably.

  According to a second aspect of the present invention, there is provided a method for manufacturing a semiconductor integrated circuit, wherein a semiconductor integrated circuit is formed on a wafer, and a unique symbol for individual recognition is formed by removing a part of a mark on the semiconductor integrated circuit. It is a feature.

  According to the method of manufacturing a semiconductor integrated circuit having the above configuration, the semiconductor integrated circuit is formed on the wafer. Since this semiconductor integrated circuit is given a unique symbol for individual recognition by removing a part of a mark, the shape of the symbol can be changed by changing the part to be erased. Therefore, a plurality of symbols having different shapes can be obtained from one mark, and a large amount of manufacturing history can be added to the semiconductor integrated circuit.

  In the method of manufacturing a semiconductor integrated circuit according to one embodiment, the symbol is a number.

  According to the method of manufacturing a semiconductor integrated circuit of the above embodiment, since the symbol is a numeral, the manufacturing history and the like can be easily and reliably recognized by looking at the symbol.

  In the method for manufacturing a semiconductor integrated circuit according to one embodiment, the symbol is formed of a visible material.

  According to the method for manufacturing a semiconductor integrated circuit of the above embodiment, since the symbol is made of a visible material, the manufacturing history and the like can be recognized more easily and reliably.

  The mask of the third invention is a mask for forming a semiconductor integrated circuit on a wafer and attaching a unique symbol for individual recognition to the semiconductor integrated circuit, and can transmit and block light irradiated on the wafer. And a terminal for externally controlling transmission and light shielding of the light by the light control unit.

  According to the mask configured as described above, the light control unit can transmit and block the light applied to the wafer. Therefore, by controlling the light applied to the wafer by the light control unit, a plurality of different symbols can be applied to the wafer. It can be formed easily. Accordingly, a large amount of manufacturing history can be added to the semiconductor integrated circuit.

  In the mask of one embodiment, the shape of the light control unit is a numerical shape.

  According to the mask of the above embodiment, since the shape of the light control unit is a numerical shape, a symbol having a numerical shape can be easily formed on the wafer.

  In the mask of one embodiment, the light control unit is formed of liquid crystal.

  According to the mask of the above embodiment, since the light control unit is formed of liquid crystal, it is possible to electrically control light transmission and light shielding in the light control unit.

  In the semiconductor integrated circuit of the first invention, the unique symbol for individual recognition is such that a part of a mark is erased, and the shape of the symbol can be changed by changing the part to be erased. Thus, a plurality of symbols having different shapes can be obtained from one mark, and a large amount of manufacturing history can be added.

  According to a second aspect of the present invention, there is provided a method for manufacturing a semiconductor integrated circuit, in which a unique symbol for individual recognition formed by erasing a part of a mark is attached to the semiconductor integrated circuit, and a part to be erased is changed. Since the shape of the symbol can be changed, a plurality of symbols having different shapes can be obtained from one mark, and a large amount of manufacturing history can be added to the semiconductor integrated circuit.

  The mask of the third invention includes a light control unit capable of transmitting and blocking light applied to the wafer, and controls the light applied to the wafer by the light control unit, thereby allowing a plurality of different symbols to be applied to the wafer. Since it can be formed easily, a large amount of manufacturing history can be added to the semiconductor integrated circuit.

  Hereinafter, a semiconductor integrated circuit manufacturing method according to the present invention will be described in detail with reference to embodiments shown in the drawings.

(First embodiment)
In the present embodiment, in an IC manufacturing process such as an LSI (Large Scale Integration), a pattern is exposed on a photoresist on a wafer using light and a pattern such as wiring is formed on the wafer. Use to create a unique number. Note that a conventional photolithography technique can be used in the method of exposing the pattern.

  FIG. 1A schematically shows a top view of a wafer 201 including a chip 202 as a semiconductor integrated circuit according to the first embodiment of the present invention. FIG. 1B is an enlarged view of the chip 202. Is shown schematically.

  The wafer 201 includes a plurality of chips 202 as shown in FIG. As shown in FIG. 1B, a manufacturing history display unit 101 for displaying a manufacturing history is formed on the surface of each of the plurality of chips 202. Further, a wiring pattern is formed in a portion other than the manufacturing history display unit 101 of the chip 202. The manufacturing history display unit 101 is formed in a region other than a region where an electrode pad (not shown) is formed on the surface of the chip 202.

  FIG. 2A schematically shows an enlarged view of the manufacturing history display unit 101 immediately after the wiring pattern is formed.

  The manufacturing history display unit 101 has a mark formed of an MR (vapor resistant) wiring layer. This mark is composed of 11 numbers 8 arranged side by side. The 1st and 2nd digit part 102 from the top of the mark is the part that should indicate the last 2 digits of the year, the 3rd and 4th digit part 103 from the top of the mark is the part that should indicate the month, A portion 104 of 5 to 8 digits from the top of the mark is a portion to indicate the serial number of the wafer 201, and a portion 105 of 9 to 11 digits from the top of the mark indicates the serial number of the chip 202 of the wafer 201. It is a power part. Such a manufacturing history display unit 101 can handle up to 10000 wafers 201 per month and 1000 chips 202 included in each wafer 201. That is, even if the wafer 201 including 1000 chips 202 is produced at 10,000 wafers / month, a unique symbol can be attached to each chip 202.

  Since such a mark is similarly formed on the manufacturing history display portion 101 of each chip 202, a symbol unique to each chip 202 is not shown. Therefore, unnecessary portions of the mark are erased with a laser to form numbers shown in FIG. 2B, for example. This number is an example of a symbol. The chip 202 to which the above number is attached was included in the wafer 201 of wafer number 2345 manufactured in September 2004 AD and is chip number 678. Note that the unnecessary portions of the mark need only be erased to such an extent that the number obtained from the mark can be visually recognized as a number, so that the accuracy of correcting the wiring pattern is not necessary.

  As described above, by assigning a different number to each of the plurality of chips 202, a unique number can be assigned to the chip 202 for each wafer or for each chip.

  Further, the mark can be changed to a number within the range of 0-99999999999 by changing the portion to be erased by the laser. Therefore, a large amount of manufacturing history can be added to the chip 202.

  Further, when the chip 202 is mounted on the substrate, it is possible to prevent the manufacturing history of the chip 202 from becoming unrecognizable simply by directing the numbered surface to the side opposite to the substrate.

  Further, by attaching the number to the chip 202, the manufacturing history of the chip 202 can be visually confirmed even after the chip 202 is shipped from the IC manufacturer. Therefore, the manufacturing history of the chip 202 can be easily and reliably recognized.

  In the first embodiment, the 11-digit manufacturing history display unit 101 is formed on the chip 202. However, the manufacturing history display unit 101 having 10 digits or less or 12 digits or more may be formed on the chip 202.

  In the first embodiment, a number indicating the wafer manufacturing history is attached to the chip 202. However, a number indicating a wafer test history, an assembly history, or the like may be attached to the chip 202.

  In the first embodiment, numerals are used as an example of symbols for individual recognition. However, letters such as English letters may be used, or a combination of numerals and letters may be used. .

  In the first embodiment, the unnecessary portion of the mark is erased by the laser, but may be erased by etching or the like.

(Second Embodiment)
FIG. 3 schematically shows a top view of the mask according to the second embodiment of the present invention.

  The mask is used to form a wafer including a chip as an example of a semiconductor integrated circuit. Specifically, the mask is used when exposing a photoresist placed on a wafer. This mask is made of a glass substrate 301, and a plurality of chip exposure regions 304 are formed on the glass substrate 301. The chip exposure region 304 includes a liquid crystal unit 302 and an IC pattern unit 303 that exhibits a shape corresponding to a wiring pattern to be formed on the chip. A liquid crystal driving segment terminal 305 and a liquid crystal driving common electrode terminal 306 as examples of terminals are connected to the liquid crystal unit 302. An external liquid crystal control device (not shown) can be connected to the liquid crystal unit 302 via the liquid crystal drive segment terminal 305 and the liquid crystal drive common electrode terminal 306. Note that a part of the IC pattern portion can sufficiently shield light applied to the wafer so that the wafer can be finely processed.

  FIG. 4 schematically shows an enlarged view of the liquid crystal unit 302.

  The liquid crystal unit 302 has eleven light control units 307 as an example of a light control unit capable of transmitting and blocking light applied to the wafer. The light control unit 307 is composed of seven portions 307a to 307g and has the shape of numeral 8. The portions 307a to 307g are made of liquid crystal, and can independently transmit and block light. That is, the portions 307a to 307g each independently transmit light or block light. The portions 307a to 307g are connected to the liquid crystal drive segment terminal 305, respectively.

  According to the mask 301 having the above-described configuration, the light applied to the photoresist under the liquid crystal unit 302 can be controlled by electrically controlling each light control unit 307. Therefore, the chip as mentioned in the first embodiment can be easily produced.

  The control method of the light control unit 307 differs depending on the material used for the portions 307a to 307g and the method for driving the portions 307a to 307g, but existing techniques can be applied.

  Further, since the portions 307a to 307g are made of liquid crystal, the light shielding by the portions 307a to 307g is not complete, and a fine pattern cannot be formed with the portions 307a to 307g, but the width of the portion 307a is large enough to create wiring. By giving it to 307 g, it is possible to add a number as described in the first embodiment to the chip.

  Moreover, since each part 307a-307g of the said light control part 307 can permeate | transmit and block light independently, even if it does not form the mark shown to Fig.2 (a) on a chip | tip, it shows, for example in FIG.2 (b). Numbers can be formed. Therefore, it is possible to eliminate the step of erasing an unnecessary portion of the mark as performed in the first embodiment, so that the manufacturing cost can be reduced.

  In the said 2nd Embodiment, although the part 307a-307g was comprised with the liquid crystal, you may comprise with materials other than a liquid crystal. Needless to say, the material is a material capable of controlling light transmission and light shielding.

  The number and arrangement of the liquid crystal units 302 and the IC pattern units 303 may be changed as appropriate according to the design.

FIG. 1A is a schematic top view of a wafer including a chip according to the first embodiment of the present invention, and FIG. 1B is a schematic enlarged view of the chip. FIG. 2A is a schematic enlarged view of a manufacturing history display unit before laser processing, and FIG. 2B is a schematic diagram of an example of numbers added to the chips. FIG. 3 is a schematic top view of a mask according to the second embodiment of the present invention. FIG. 4 is a schematic enlarged view of the liquid crystal portion of the mask.

Explanation of symbols

101 Manufacturing History Display Unit 201 Wafer 202 Chip 305 Liquid Crystal Drive Segment Terminal 306 Liquid Crystal Drive Common Electrode Terminal 307 Light Control Unit

Claims (9)

In a semiconductor integrated circuit with a unique symbol for individual recognition,
A semiconductor integrated circuit characterized in that a part of the mark is erased. The semiconductor integrated circuit according to claim 1,
A semiconductor integrated circuit, wherein the symbol is a number. The semiconductor integrated circuit according to claim 1,
A semiconductor integrated circuit, wherein the symbol is formed of a visible material.   A method of manufacturing a semiconductor integrated circuit, wherein a semiconductor integrated circuit is formed on a wafer, and a unique symbol for individual recognition is formed by removing a part of a mark on the semiconductor integrated circuit. In the manufacturing method of the semiconductor integrated circuit according to claim 4,
A method of manufacturing a semiconductor integrated circuit, wherein the symbol is a number. In the manufacturing method of the semiconductor integrated circuit according to claim 4,
The symbol is formed of a visible material, and a method for manufacturing a semiconductor integrated circuit. In a mask for forming a semiconductor integrated circuit on a wafer and attaching a unique symbol for individual recognition to the semiconductor integrated circuit,
A light control unit capable of transmitting and blocking light applied to the wafer;
A mask comprising: a terminal for externally controlling transmission and light shielding of the light by the light control unit. The mask according to claim 7, wherein
A mask characterized in that the shape of the light control unit is a numerical shape. The mask according to claim 7, wherein
The mask, wherein the light control unit is formed of liquid crystal.

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