CN-114639596-B - Method for regulating and controlling defects and doping characteristics of wide forbidden band semiconductor material

Abstract

In order to overcome the problems that the existing wide-bandgap semiconductor material has a large number of spontaneous defects, an intrinsic semiconductor is difficult to obtain and inversion doping is difficult to realize, the invention discloses a method for controllably improving the formation energy of spontaneous defects and simultaneously reducing the formation energy of inversion doping defects through externally applied voltage to realize the preparation and inversion doping of the intrinsic wide-bandgap semiconductor material. The method comprises the following operation steps of applying a positive bias to a wide band gap semiconductor material spontaneously forming N-type conductivity and applying a negative bias to a wide band gap semiconductor material spontaneously forming P-type conductivity in the process of growing an intrinsic wide band gap semiconductor material and inversely doping. The invention also discloses application of the method in preparing intrinsic zinc oxide and P-type doped zinc oxide.

Inventors

• LUO GUANGFU
• LIU KAI

Assignees

• 南方科技大学

Dates

Publication Date

20260512

Application Date

20200922

Claims (4)

1. 1. A method for regulating and controlling defects and doping characteristics of a wide-bandgap semiconductor material is characterized in that the wide-bandgap semiconductor material is ZnO material, a preparation bias voltage is applied to a zinc oxide generation area through a hydrothermal method, a fusion method or a molecular beam epitaxial growth mode, and the wide-bandgap semiconductor material is grown under the preparation bias voltage applied by an electrode, wherein the preparation bias voltage is 1-3V; And covering an external electrode on one side surface of the wide band gap semiconductor material, applying a doping bias voltage to the wide band gap semiconductor material through the external electrode, and performing inversion doping treatment on the other side surface, wherein the doping bias voltage is 1-3 volts.
2. 2. The method of claim 1, wherein the morphology of the wide bandgap semiconductor material comprises single crystals, thin films, or nanostructures.
3. 3. Use of the method according to any one of claims 1-2 for the preparation of P-doped zinc oxide single crystals, films or nanostructures.
4. 4. The use of claim 3, wherein the doping element comprises one or more of Li, na, ag, N, P, as.

Description

Method for regulating and controlling defects and doping characteristics of wide forbidden band semiconductor material Technical Field The invention belongs to the technical field of semiconductor materials, and particularly relates to a method for regulating and controlling defects and doping characteristics of a wide bandgap semiconductor material and application thereof. Background The wide forbidden band semiconductor, such as gallium nitride (GaN), aluminum nitride (AlN), silicon carbide (SiC), zinc oxide (ZnO), gallium oxide (Ga 2O3) and other materials, has the characteristics of large energy gap, high breakdown voltage, strong radiation resistance, high thermal conductivity, high electron mobility and the like, is very suitable for manufacturing high-voltage, high-temperature, high-frequency and high-power electronic devices, and light emitting and light detecting devices of visible light and ultraviolet light, and has wide application prospect. Unlike conventional semiconductor materials, most of the wide bandgap semiconductor materials prepared by the current experiments exhibit very strong N-type or P-type conductivity due to a large number of spontaneously formed defects, and it is difficult to realize opposite conductivity by conventional doping methods. Therefore, the preparation of an intrinsic semiconductor with low defect concentration and the realization of high-efficiency inversion doping are key to the further development of wide-bandgap semiconductor devices. Under the condition that a large number of spontaneous defects are not effectively eliminated, the efficiency of the related inversion doping is greatly reduced at present, namely the inversion carrier concentration obtained under the normal doping concentration is extremely low, and the heavy doping can improve the inversion carrier concentration, but the mobility is extremely low due to the excessively high defect concentration at the moment. For example, researchers in the United states of America Solid STATE SCIENTIFIC in 2006 studied the P-type doping characteristics in nitrogen-doped ZnO films using a hydrothermal method, and as a result found that when the nitrogen atom doping concentration reached 10 18cm-3, the activated P-type concentration was only 10 12cm-3, and the hole mobility was as low as 11 cm 2/V ∙ s. The above-mentioned dilemma makes it difficult to realize a homogenous P-N junction device based on these wide bandgap semiconductor materials. These wide bandgap semiconductor devices, which are difficult to inversely dope, often need to be based on heterogeneous P-N junctions. However, the preparation process of the heterojunction device is complex, and the interface has more defects due to lattice mismatch among different materials, so that the price, the performance and the service life of the device are seriously affected. The above-mentioned problems with wide bandgap semiconductor materials are essentially determined by the thermodynamic properties of crystal defects in the material. According to thermodynamic definition, a crystal point defect of general significance(I.e., the atom of element A occupies the position of the B lattice point in the crystal, and the defect has a charge q) the defect formation can be as shown in formula 1. (1) Wherein, the AndRespectively indicate that there are defectsThe internal energy of the crystalline material and the corresponding perfect crystalline material,Mu A and mu B are chemical potentials of the A and B elements under relevant experimental conditions, which are fermi levels of the crystals. More complex crystal defects can be seen as consisting of a plurality of point defects, thus following a thermodynamic law similar to that of point defects. Formation energy of defectInversely proportional to the concentration c of the defect in the crystal, the specific form is shown in formula 2. (2) Wherein, the For a number density of defects in the crystal that may form in relation,For the formation energy of the relevant defect,Is a boltzmann constant,The absolute temperature at which defects form is typically the material growth temperature. The fermi level of the material can be determined self-consistently by formulas (1) and (2) and the electric neutrality principle (i.e. the sum of the charges of all charged defects, electrons and holes in the crystal is zero) that the material of the crystal satisfies, so as to judge the doping type and the conductive property of the material under various conditions, as shown in formula 3. (3) Wherein, the And (3) withRespectively the semiconductor material has a Fermi level ofThe carrier measurement temperature isThe free electron and hole concentrations at the time are,Is a defectIs a concentration of (3). Disclosure of Invention Aiming at the problems that the existing wide bandgap semiconductor has a large number of spontaneous defects, intrinsic semiconductor is difficult to obtain and inversion doping is difficult to realize,