Process for producing silicon carbide crystals having increased minority carrier lifetimes
View Patent ↗A process is described for producing silicon carbide crystals having increased minority carrier lifetimes. The process includes the steps of heating and slowly cooling a silicon carbide crystal having a first concentration of minority carrier recombination centers such that the resultant concentration of minority carrier recombination centers is lower than the first concentration.
1. A silicon carbide single crystal wafer having a minority carrier lifetime of at least 20 microseconds.
2. The silicon carbide single crystal wafer of claim 1 further comprising an epitaxial layer.
3. The silicon carbide single crystal of claim 1 , wherein said wafer has a minority carrier lifetime of at least about 30 microseconds.
4. The silicon carbide single crystal wafer of claim 3 further comprising an epitaxial layer.
5. A semiconductor device comprising:
a silicon carbide single crystal substrate having a minority carrier lifetime of at least 20 microseconds; and
at least one epitaxial layer.
6. The semiconductor device of claim 5 wherein said device is a power device.
7. The semiconductor device of claim 6 wherein said device is selected from the group consisting of a pn diode, a PiN diode, a thyristor and an IGBT.
8. The semiconductor device of claim 5 , wherein said substrate has a minority carrier lifetime of at least about 30 microseconds.
9. The semiconductor device of claim 8 wherein said device is a power device.
10. The semiconductor device of claim 9 wherein said device is selected from the group consisting of a pn diode, a PiN diode, a thyristor and an IGBT.
11. A diode comprising:
a p type layer;
an n type layer; and
a silicon carbide intrinsic layer sandwiched in between the p type layer and the n type layer wherein the minority carrier lifetime of the intrinsic layer is at least 20 microseconds.
12. The silicon carbide single crystal of claim 11 , wherein said intrinsic layer has a minority carrier lifetime of at least about 30 microseconds.