High-k Based Metal Oxide Device with Light Emitting Applications
Abstract
The electrical and optical characteristics of the ZrHfO, WOx, WOx embedded ZrHfO solid state incandescent light emission devices (SSI-LED) have been explored. SSI-LED is made from the high-k MOS capacitor after the dielectric breakdown takes place in oxide layer. Therefore, the electrical properties such as interface defect density, oxide trapped charge density, equivalent oxide thickness, and leakage current density of SSI-LED have been investigated along with oxygen and nitrogen PDA to obtain excellent light emitting properties. Since ZrHfO high-k material has superb gate dielectric properties, e.g., high crystallization temperature, low interface state density, oxide trapped charges, and high effective k value, it has been used into MOS capacitor to obtain great performance. Applying the gate voltage above certain magnitude, i.e. breakdown voltage, the ZrHfO SSI-LED forms and emits the warm white light with high color rendering index (CRI, very close to 100) and low color correlated temperature (CCT) comparing to the commercial YAG:Ce white LED. On the other hand, the WOx MOS capacitor as well as SSI-LED has been studied. The increased light intensity is observed due to the high emissivity coefficient of tungsten component; however, the reliability concern may arise from the high leakage current. Therefore, the three-layer WOx embedded ZrHfO high-k stack is introduced. With the including of tungsten into ZrHfO bulk oxide, the great capacitor characteristics have been preserved, and emission intensity of SSI-LED has been increased as well. In addition, the environmental factors, i.e. humidity and temperature, and gate material influence on the MOS capacitor has been examined.
Citation
Lin, Wen-Shan (2020). High-k Based Metal Oxide Device with Light Emitting Applications. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /192873.