Role of electric fields in enhancing the doping of semiconductors during epitaxial growth
- Univ. of Toledo, OH (United States)
A novel technique is described to enhance the doping in semiconductors by the application of external electric fields during crystal growth. The authors show that this technique can enhance the doping efficiency, and suppress self-compensation processes in novel growth techniques such as molecular-beam epitaxy (MBE). An obvious application of this technique is to enhance the doping of wide band gap II-VI semiconductors, where doping in both n- and p-types is usually not possible to achieve because of extensive self-compensation. The physics of the electric field assisted doping process can be described in two parts. First, the external electric field produces a change in the band bending at the growth surface and alters the carrier concentrations near the surface region. This influences doping near the surface region. Second, this enhanced surface doping concentration can be kinetically buried by low temperature growth processes. In their calculations, the dopants are modeled as charged, mobile species that are free to diffuse and drift under electric fields. In the case of MBE growth, they solve for the equilibrium of these species in a moving coordinate frame that travels with the growth front. They have specially applied their analysis to Li donors in n-type ZnTe. Their results indicate that excellent improvements in the doping concentrations could be obtained under normal MBE growth conditions, with the application of substantial electric fields. They expect that their analysis, and the proposed electric field assisted doping technique will play an important role in the effort to overcome compensation, and achieve selective doping in wide band gap II-VI semiconductors.
- OSTI ID:
- 7306156
- Report Number(s):
- CONF-910115-; CODEN: JVTBD
- Journal Information:
- Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States), Vol. 9:4; Conference: 18. annual conference on physics and chemistry of semiconductor interfaces, Long Beach, CA (United States), 29 Jan - 1 Feb 1991; ISSN 0734-211X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Growth of highly doped p-type ZnTe films by pulsed laser ablation in molecular nitrogen
Good electrical contacts for high resistivity (Cd,Mn)Te crystals
Related Subjects
N-TYPE CONDUCTORS
CRYSTAL DOPING
ZINC TELLURIDES
MOLECULAR BEAM EPITAXY
CRYSTAL GROWTH
DOPED MATERIALS
ELECTRIC FIELDS
GRADED BAND GAPS
LITHIUM
MATHEMATICAL MODELS
ALKALI METALS
CHALCOGENIDES
ELEMENTS
EPITAXY
MATERIALS
METALS
SEMICONDUCTOR MATERIALS
TELLURIDES
TELLURIUM COMPOUNDS
ZINC COMPOUNDS
360601* - Other Materials- Preparation & Manufacture