Nitride-based semiconductor substrate and semiconductor device
View Patent ↗A nitride-based semiconductor substrate has a diameter of 25 mm or more, a thickness of 250 micrometers or more, a n-type carrier concentration of 1.2×10 18 cm −3 or more and 3×10 19 cm −3 or less, and a thermal conductivity of 1.2 W/cmK or more and 3.5 W/cmK or less. Alternatively, the substrate has an electron mobility μ [cm2/Vs] of more than a value represented by log e μ=17.7−0.288 log e n and less than a value represented by log e μ=18.5−0.288 log e n, where the substrate has a n-type carrier concentration n [cm −3 ] that is 1.2×10 18 cm −3 or more and 3×10 19 cm −3 or less.
1. A nitride-based semiconductor substrate, comprising:
a substrate comprising a nitride-based semiconductor,
wherein the substrate comprises:
a diameter of 25 mm or more;
a thickness of 250 micrometers or more;
a dislocation density of 1×10 7 cm −2 or less;
an oxygen impurity concentration of 10 16 cm −3 or less;
an n-type carrier concentration in a range of 1.2×10 18 cm −3 to 3×10 19 cm −3 ; and
a thermal conductivity in a range of 1.2 W/cmK to 3.5 W/cmK.
2. The nitride-based semiconductor substrate according to claim 1 , wherein:
the substrate comprises an electrical resistivity of 0.001 ohm·cm or more and 0.02 ohm·cm or less.
3. The nitride-based semiconductor substrate according to claim 1 , wherein the substrate comprises a concentration of As, Cl, P, Na, K, Li, Ca, Sn, Ti, Fe, Cr and Ni to be all 1×10 17 cm −3 or less.
4. A semiconductor device, comprising:
the nitride-based semiconductor substrate as defined in claim 1 ; and
a nitride-based semiconductor layer grown epitaxially on the nitride-based semiconductor substrate.