Summary: | 碩士 === 國立中興大學 === 物理學系 === 91 === This thesis is about the process of fabricating a narrow channel on Si/SiGe heterostructures containing a heavily doped boron layer. We use the photolithography technique for the Hall pattern and the e-beam lithography technique to define the narrow channel. Because the boron d-doping of the sample, we have to use a very strong wet-etching solution to do the mesa etching. The PMMA can not block the etching solution for mesa etching. Therefore, we transferred the narrow channel pattern to a Au/Ti metal layer which serves as both the etching mask and the gate. We successfully made a device with a 2micro narrow channel.
We investigated the electric properties of the device. The I-V characteristics at the room temperature and 11K are measured, including the effect of the gate bias. From the result of our measurement, we found that: (1) the lowest resistance between ohmic contacts was 5kohm at room temperature, and 80kohm at 11K. (2) the gate on the Si/SiGe heterostructure sample N492 has a serious electric leakage, probably due to the heavy boron doping.
|