Source: https://patents.google.com/patent/US8143141B2/en
Timestamp: 2018-11-19 04:02:14
Document Index: 90112901

Matched Legal Cases: ['art 16', 'art 7', 'art 16', '§371', 'art 16', 'art 16', 'art 16', 'art 7', 'art 7', 'art 7']

US8143141B2 - Laser beam machining method and semiconductor chip - Google Patents
Laser beam machining method and semiconductor chip Download PDF
US8143141B2
US8143141B2 US12882787 US88278710A US8143141B2 US 8143141 B2 US8143141 B2 US 8143141B2 US 12882787 US12882787 US 12882787 US 88278710 A US88278710 A US 88278710A US 8143141 B2 US8143141 B2 US 8143141B2
US12882787
US20110001220A1 (en )
A laser processing method is provided, which, when cutting a substrate formed with a multilayer part including a plurality of functional devices, makes it possible to cut the multilayer part with a high precision in particular.
In a state where a protective tape 22 is attached to the front face 16 a of a multilayer part 16, a substrate 4 is irradiated with laser light L while using its rear face 4 b as a laser light entrance surface, so as to form a modified region 7 within the substrate 4 along a line to cut, thereby generating a fracture 24 reaching the front face 4 a of the substrate 4 from a front-side end part 7 a of the modified region 7. Attaching an expandable tape to the rear face 4 b of the substrate 4 and expanding it in the state where such a fracture 24 is generated can cut not only the substrate 4 but also the multilayer part 16 on the line to cut, i.e., interlayer insulating films 17 a , 17 b, with a favorable precision along the line to cut.
This is a continuation application of copending application Ser. No. 11/667,596, having a §371 date of Aug. 15, 2007 U.S. Pat. No. 7,902,636, which is a national stage filing based on PCT International Application No. PCT/JP2005/020627, filed on Nov. 10, 2005. The copending application Ser. No. 11/667,596 is incorporated by reference herein in its entirety.
Preferably, the substrate has a thickness of 30 μm to 150 μm. When the thickness of the substrate is 30 μm to 150 m, not only the multilayer part but also the substrate can be cut with a high precision from the above-mentioned modified region as a start point.
In still another aspect, the laser processing method in accordance with the present invention, is a laser processing method of irradiating a substrate having a front face formed with a multilayer part including a plurality of functional devices with laser light while locating a converging point within the substrate, so as to form a modified region to become a starting point region for cutting within the substrate along a line to cut in the substrate, wherein the modified region is formed such that the distance between a position of a front-side end part of the modified region and the front face of the substrate is 3 μm to 40 μm.
FIG. 17 plan view of the object to be processed in the laser processing method in accordance with the embodiment.
laser light spot cross-sectional area: 3.14×104 cm2
laser light spot cross-sectional area: 3.14×10−8 cm2 oscillation mode: Q-switched pulse
An object to be processed (e.g., semiconductor material such as silicon) is irradiated with laser light while locating a converging point within the object under a condition with a field intensity of at least ×108 (W/cm2) at the converging point and a pulse width of 1 ns is or less. This may form a molten processed region and a microcavity within the object. The upper limit of field intensity is 1×1012 (W/cm2), for example. The pulse width is preferably 1 ns to 200 ns, for example.
As shown in FIGS. 17 and 18, the object 1 comprises a substrate 4 having a thickness of 30 μm to 150 μm made of silicon, and a multilayer part 16, formed on the front face 4 a of the substrate 4, including a plurality of functional devices 15. Each functional device 15 has an interlayer insulating film 17 a laminated on the front face 4 a of the substrate 4, a wiring layer 19 a formed on the interlayer insulating film 17 a, an interlayer insulating film 17 b laminated on the interlayer insulating film 17 a so as to cover the wiring layer 19 a, and a wiring layer 19 b formed on the interlayer insulating film 17 b. The wiring layer 19 a and the substrate 4 are electrically connected to each other by a conductive plug 20 a penetrating through the interlayer insulating film 17 a, whereas the wiring layers 19 a and 19 b are electrically connected to each other by a conductive plug 20 b penetrating through the interlayer insulating film 17 b.
While a number of functional devices 15 are formed like a matrix in directions parallel and perpendicular to an orientation flat 6 of the substrate 4, the interlayer insulating films 17 a, 17 b are formed between the functional devices 15, 15 adjacent to each other so as to cover the front face 4 a of the substrate 4 as a whole.
After peeling off the protective tape 22, the expandable tape 23 is expanded as shown in FIG. 21( b), so as to cause a break from the modified region 7 acting as a start point, thereby cutting the substrate 4 and multilayer part 16 along the lines to cut 5 and separating semiconductor chips 25 obtained by cutting from each other. This can yield the semiconductor chips 25 each comprising the substrate 4 and the multilayer part 16, formed on the front face 4 a of the substrate 4, including the functional device 15, whereas the modified region 7 is formed on a side face 4 c of the substrate 4 such that the distance between the position of the front-side end part 7 a and the front face 4 a of the substrate 4 is 3 μm to 40 μm.
Therefore, the state where the fracture 24 reaching the front face 4 a of the substrate 4 from the front-side end part 7 a of the modified region 7 is generated seems to be able to cut the low dielectric constant film 26 with a higher precision together with the substrate 4 than the state where the fracture 24 reaching the rear face 4 b of the substrate 4 from the rear-side end part 7 b of the modified region 7 is generated.
irradiating a substrate having a front face formed with a multilayer part including a plurality of functional devices with laser light while locating a converging point within the substrate;
as a result of the irradiating of the substrate, forming a modified region serving as a starting point region for cutting within the substrate along a cutting line in the substrate; and
generating a fracture reaching the front face of the substrate or inside of the multilayer part from a front-side end part of the modified region.
2. A laser processing method according to claim 1, wherein the modified region is formed such that the front-side end part of the modified region extends like a streak to the front face of the substrate.
3. A laser processing method according to claim 1, wherein the substrate is a semiconductor substrate, and wherein the modified region includes a molten processed region.
4. A laser processing method according to claim 1, wherein the substrate is a semiconductor substrate, and wherein the modified region includes a molten processed region and a microcavity positioned closer to the front face of the substrate than is the molten processed region.
5. A laser processing method according to claim 1, wherein the substrate has a thickness of 30 μm to 150 μm.
6. A laser processing method according to claim 1, wherein the substrate and multilayer part are cut along the cutting line after forming the modified region.
7. A laser processing method according to claim 1, wherein the modified region is formed such that the distance between a position of a front-side end part of the modified region and the front face of the substrate is 3 μm to 40 μm.
8. A laser processing method according to claim 7, wherein the modified region is formed such that the distance between the position of the front-side end part of the modified region and the front face of the substrate is 3 μm to 35 μm when the laser light is irradiated once along the cutting line.
9. A laser processing method according to claim 7, wherein the front-side end part of the modified region and the front face of the substrate is 3 μm to 40 μm when the laser light is irradiated a plurality of times along the cutting line.
US12882787 2004-11-12 2010-09-15 Laser beam machining method and semiconductor chip Active US8143141B2 (en)
JPP2004-329560 2004-11-12
JP2004329560A JP4917257B2 (en) 2004-11-12 2004-11-12 Laser processing method
PCT/JP2005/020627 WO2006051866A1 (en) 2004-11-12 2005-11-10 Laser beam machining method and semiconductor chip
US66759607 true 2007-08-15 2007-08-15
US12882787 US8143141B2 (en) 2004-11-12 2010-09-15 Laser beam machining method and semiconductor chip
US11667596 Continuation
PCT/JP2005/020627 Continuation WO2006051866A1 (en) 2004-11-12 2005-11-10 Laser beam machining method and semiconductor chip
US66759607 Continuation 2007-08-15 2007-08-15
US20110001220A1 true US20110001220A1 (en) 2011-01-06
US8143141B2 true US8143141B2 (en) 2012-03-27
ID=36336543
US11667596 Active 2027-09-07 US7902636B2 (en) 2004-11-12 2005-11-10 Semiconductor chip including a substrate and multilayer part
US12882787 Active US8143141B2 (en) 2004-11-12 2010-09-15 Laser beam machining method and semiconductor chip
US (2) US7902636B2 (en)
EP (1) EP1811551B1 (en)
JP (1) JP4917257B2 (en)
KR (3) KR101282459B1 (en)
CN (1) CN100487868C (en)
WO (1) WO2006051866A1 (en)
DE102012003747B4 (en) 2011-03-01 2016-08-18 Infineon Technologies Austria Ag A method for producing a semiconductor device
JPS53114347A (en) 1977-12-07 1978-10-05 Toshiba Corp Working method for semiconductor device
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JP2005057257A (en) 2003-07-18 2005-03-03 Hamamatsu Photonics Kk Laser machining method and device, and machined product
JP2006140354A (en) 2004-11-12 2006-06-01 Hamamatsu Photonics Kk Laser processing method
US20070170159A1 (en) 2003-07-18 2007-07-26 Hamamatsu Photonics K.K. Laser beam machining method, laser beam machining apparatus, and laser beam machining product
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EP1670046A1 (en) 2003-09-10 2006-06-14 Hamamatsu Photonics K. K. Semiconductor substrate cutting method
EP1811551B1 (en) 2014-01-08 grant
CN100487868C (en) 2009-05-13 grant
WO2006051866A1 (en) 2006-05-18 application
JP4917257B2 (en) 2012-04-18 grant
JP2006140355A (en) 2006-06-01 application
KR20130016406A (en) 2013-02-14 application
US7902636B2 (en) 2011-03-08 grant
EP1811551A4 (en) 2009-07-29 application
US20110001220A1 (en) 2011-01-06 application
US20090212396A1 (en) 2009-08-27 application
KR101282509B1 (en) 2013-07-04 grant
KR101282459B1 (en) 2013-07-04 grant
CN101057317A (en) 2007-10-17 application
KR20070086026A (en) 2007-08-27 application
KR20130016407A (en) 2013-02-14 application
KR101282432B1 (en) 2013-07-04 grant
EP1811551A1 (en) 2007-07-25 application
US20060148212A1 (en) 2006-07-06 Method for cutting semiconductor substrate