Gallium—nitride-on-diamond wafers and devices, and methods of manufacture
Methods for integrating wide-gap semiconductors, and specifically, gallium nitride epilayers with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure that comprises at least one layer made out of gallium nitride. Methods for manufacturing GaN-on-diamond wafers with low bow and high crystalline quality are disclosed along with preferred choices for manufacturing GaN-on-diamond wafers and chips tailored to specific applications.
1. A device comprising:
a first diamond layer having a first thickness and a first lateral dimension;
a second diamond layer having a second thickness and a second lateral dimension;
a buried metal layer sandwiched between said first diamond layer and second diamond layer;
a semiconductor layer;
a dielectric layer sandwiched between said semiconductor layer and said second diamond layer;
at least one electrical contact disposed on the surface of said semiconductor layer; and
at least one metalized via.
2. The device of claim 1 , wherein said metalized via extends from said at least one electrical contact to said buried metal layer.
3. The device of claim 1 , wherein said semiconductor layer at least in part comprises of gallium nitride.
4. The device of claim 1 , wherein said dielectric layer is made out of amorphous silicon nitride.
5. The device of claim 2 , wherein said first lateral dimension and said second lateral dimension are substantially equal.
6. The device of claim 2 , wherein said first thickness is larger than the said second thickness.
7. The device of claim 1 , wherein said first thickness is between 20 micrometers and 200 micrometers.
8. The device of claim 1 further comprising a back-side metal layer adjacent to said first diamond layer.
9. The device of claim 8 , wherein said at least one metalized via extends from said buried metal layer to said back-side metal layer.
10. The device of claim 8 , wherein said at least one metalized via extends from said at least one electrical contact to said back-side metalized layer.
11. The device of claim 2 , wherein said device is one of a group comprising of high-electron mobility transistor, microwave integrated circuit, mixing diode, switching diode, and transmission line.
12. The device of claim 1 , wherein said second diamond layer has thickness between 0.02 mm and 0.3 mm.
13. The device of claim 1 , wherein said first diamond layer has thickness between 0.2 mm and 1.5 mm.
14. The device of claim 1 , wherein said buried metal layer has thickness between 0.01 mm and 0.05 mm.