4.6 Article

Approach to achieving a p-type transparent conducting oxide: Doping of bismuth-alloyed Ga2O3 with a strongly correlated band edge state

Journal

PHYSICAL REVIEW B
Volume 103, Issue 11, Pages -

Publisher

AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.103.115205

Keywords

-

Funding

  1. Nature Science Foundation of China [11634003, 11991060, U1930402]
  2. Key Research & Development Program of Beijing [Z181100005118003]
  3. National Science Foundation under the Early Career Development Program [DMR-1652994]
  4. China Scholarship Council [201904890014]
  5. XSEDE supercomputer facility under National Science Foundation [ACI-1053575]

Ask authors/readers for more resources

This study proposes efficient p-type doping in transparent oxides by adding a small amount of Bi2O3 into Ga2O3 to form dilute (BixGa1-x)(2)O-3 alloys. The addition of Bi raises the intermediate valence band energy, facilitating p-type doping, with commonly expected shallow acceptors showing deeper levels in the alloy. This understanding provides insights into doping semiconductor materials with a strongly correlated band edge state.
P-type doping in oxides is usually difficult due to their low valence-band energy. In order to make them p type, the electronic structure of the oxides should be fundamentally changed; that is, the occupied valence band should be raised significantly. Here, using first-principles calculations, we propose that by adding a small amount of Bi2O3 into Ga2O3 to form dilute (BixGa1-x)(2)O-3 alloys and, more importantly, with properly chosen dopants, we can achieve efficient p-type doping in a transparent oxide. We show that adding a few percent of Bi to Ga2O3 leads to an intermediate valence band that is sufficiently high in energy to facilitate p-type doping; however, the commonly expected shallow acceptors, Mg and Zn substitution on the Ga site (Mg-Ga and Zn-Ga), are still deep acceptors, whereas the expected deep acceptor, Cu-Ga, actually creates a relatively shallow level in (BixGa1-x)(2)O-3 alloys. This trend is opposite to what is found in pure Ga2O3. The puzzling behavior of the acceptor levels in the (BixGa1-x)(2)O-3 alloys is attributed to the polaronic character of the holes in the Zn- and Mg-doped cases, and the decoupling of the hole state and the valence-band edge in the Cu-doped case. This understanding provides insights into the realization of p-type doping in dilute (BixGa1-x)(2)O-3 alloys and paves a way to dope semiconductor materials with a strongly correlated band edge state, i.e., materials with a tendency to form polaronic acceptor or donor states.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.6
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available