SCRIBING A WAFER OF SEMICONDUCTOR DEVICES
Embodiments of the invention include a method for separating a wafer including a growth substrate and a plurality of devices formed on the growth substrate and arranged in a plurality of rows separated by at least one street. The wafer includes a front side on which the plurality of devices are formed and a back side, which is a surface of the growth substrate. The method includes scribing a first scribe line aligned with the street on the front side, scribing a second scribe line aligned with the street on the back side, and scribing a third scribe line aligned with the street on the back side.
1 . A method for separating a wafer comprising a growth substrate and a plurality of devices formed on the growth substrate and arranged in at least two rows separated by at least one street(s), the wafer comprising a front side on which the plurality of devices are formed and a back side comprising a surface of the growth substrate, the method comprising:
scribing a first scribe line aligned with a first street from the at least one street(s) on the front side;
scribing a second scribe line aligned with the first street on the back side; and
scribing a third scribe line aligned with the first street on the back side.
2 . The method of claim 1 wherein scribing a first scribe line comprises ablation scribing the first scribe line.
3 . The method of claim 1 wherein:
the first street comprises material epitaxially grown on the growth substrate;
the first scribe line has a depth that extends into the growth substrate; and
the depth extending into the growth substrate is at least the thickness of the material epitaxially grown on the growth substrate.
4 . The method of claim 1 wherein:
the first street comprises material epitaxially grown on the growth substrate;
the first scribe line has a depth that extends into the growth substrate; and
the depth extending into the growth substrate is no more than three times the thickness of the material epitaxially grown on the growth substrate.
5 . The method of claim 1 wherein the growth substrate has a thickness greater than 200 microns.
6 . The method of claim 1 wherein the first street has a width less than 50 microns.
7 . The method of claim 1 wherein:
scribing a second scribe line comprises forming a first modified region within the growth substrate;
scribing a third scribe line comprises forming a second modified region within the growth substrate; and
the first modified region is at a different depth in the growth substrate than the second modified region.
8 . The method of claim 7 further comprising scribing a fourth scribe line aligned with the first street on the back side, wherein scribing a fourth scribe line comprises forming a third modified region within the growth substrate, wherein the third modified region is at a different depth in the growth substrate than the first and second modified regions.
9 . A method for separating a wafer comprising a growth substrate and a plurality of devices formed on the growth substrate and arranged in a plurality of rows separated by at least one street(s), the wafer comprising a front side on which the plurality of devices are formed and a back side comprising a surface of the growth substrate, the method comprising:
scribing a first scribe line aligned with a first street from the at least one street(s) on the front side; and
scribing a second scribe line aligned with the first street on the back side; wherein:
the growth substrate has a thickness greater than 100 microns; and
the first street has a width less than 50 microns.
10 . The method of claim 9 wherein scribing a first scribe line comprises ablation scribing the first scribe line and scribing the second scribe line comprises stealth scribing the second scribe line.
11 . The method of claim 9 further comprising scribing a third scribe line aligned with the first street on one of the front and back sides.
12 . A method for separating a wafer comprising a growth substrate and a plurality of devices formed on the growth substrate and arranged in a plurality of rows separated by at least one street(s), the wafer comprising a front side on which the plurality of devices are formed and a back side comprising a surface of the growth substrate, the method comprising:
scribing a first scribe line aligned with a first street from the at least one street(s); and
scribing a second scribe line aligned with the first street, wherein the first and second scribe lines are both formed on the same side of the wafer.
13 . The method of claim 12 wherein the first and second scribe lines are both formed on the back side of the wafer.
14 . The method of claim 12 wherein:
scribing a first scribe line comprises forming a first modified region within the growth substrate;
scribing a second scribe line comprises forming a second modified region within the growth substrate; and
the first modified region is at a different depth in the growth substrate than the second modified region.
15 . The method of claim 12 wherein the first scribe line is disposed over the second scribe line.
16 . The method of claim 12 further comprising scribing a third scribe line aligned with the first street, wherein the third scribe line is formed on the same side of the wafer as the first and second scribe lines.