CN1122520A

CN1122520A - Metal semiconductor compound film with high photoelectronic conversion efficiency

Info

Publication number: CN1122520A
Application number: CN 94119274
Authority: CN
Inventors: 解青华
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-12-20
Filing date: 1994-12-20
Publication date: 1996-05-15

Abstract

The compound film features that on the semiconductor layer of the function of separating and collecting electrons, there is a superfine particle layer of metal and/or semiconductor. When the size of superfine particles meets the resonance absorption condition, they form multiple vertical-junction quantum trap. The stimulated electrons after absorbing photons tunnel to the bottom semiconductor layer, where they are separated and collected to complete the optoelectronic conversion. The said new optoelectronic conversion course has high efficiency not limited by the limit in semiconductor energy band theory.

Description

The half of metal conductor composite membrane of high-photoelectric transformation efficiency

The present invention relates to a kind of half of metal conductor structure of composite membrane that utilizes the opto-electronic conversion new principle to carry out efficient opto-electronic conversion.

The photoelectricity transformation principle of traditional semiconductor solar cell is to utilize semi-conductive can being with, absorb the light wave of corresponding energy, producing photo-generated carrier is that electronics one hole is right, under the effect of the built-in field that is subjected to semiconductor PN or semiconductor depletion layer, be separated to the upper/lower electrode of solar cell, and finish the process of opto-electronic conversion.So far, there is low and the problem that cost is high of photoelectric conversion efficiency based on the various solar cells of this principle manufacturing.

The present invention is the small-size effect of the ultrafine dust in the thin metal layer that utilizes on the whole face that is subjected to illumination in the top of the PN junction be manufactured on semiconductor solar cell or depletion layer.Because ultrafine dust size and physical sizes such as wavelength light wave or microwave or conduction electron de Broglie wavelength are quite or more hour, produce resonant absorption effects and destroyed owing to the periodic boundary condition of crystal, rerum naturas such as sound, light, electromagnetism, thermodynamics all will present small-size effect.Here the size range of said ultrafine dust: during as opto-electronic conversion, must be for (annotate: nanometer is a kind of tiny length unit, 1 nanometer=10 between 1 nanometer to 300 nanometer ^-9Rice); Must be when absorbing microwave energy and convert electric energy to for about about 300 nanometers to 1 micron.

Because the electron effective mass in the metal is little, under the effect of the electromagnetism wave vector of light wave or microwave, quicken rapidly, become excited electron after producing resonance absorption, simultaneously, when contained atom number reduces along with reducing of particle size in the metal particle, near its Fermi level electron energy level will split into discrete energy levels by quasi-continuous attitude, therefore, offer a large amount of electronics with endergonic chance in than wide spectral range.Its absorptivity can reach more than 90%, can form a large amount of excited electrons.That on the other hand, utilizes metal is the effects such as vertical multiple knot that produced of evenly distributing alternately with semi-conductive or semi-conductive ultrafine dust that two kinds of bandwidths are different and the efficient that luminous energy (or microwave energy) is absorbed is heightened and the energy that converts excited electron in being mixed and made into the above-mentioned thin layer that is subjected to illumination.According to the quantum mechanics theory of solids, for about 2-3 the heat insulating lamina below the nano thickness, electronics has the ability of tunneling barrier.Here said potential barrier comprises ultrafine dust intermetallic potential barrier, thin metal layer and the semiconductor interlayer insulating film potential barrier below it, and semiconductor depletion layer potential barrier etc.Electronics behind the tunneling barrier is collected bottom electrode by the semiconductor PN below the thin metal layer or the built-in field of semiconductor depletion layer, thereby finishes light (or microwave)-electric transfer process.

The new principle and the structure that propose according to the present invention can be designed to various light (or microwave)-power conversion device.Can determine respectively as the case may be as for the kind of metal that specifically in device, is adopted or semi-conducting material, size, shape, film thickness etc.For above-mentioned device, utilize existing technology (as SEMICONDUCTING THIN FILM TECHNOLOGY, thick-film technique etc.) might carry out the manufacturing of some device, but some required process equipment and technology also need be specialized in.Then await utilizing the atomic engineering technology that is developing for more perfect designs and process manufacturing technology, promptly can arrange the technology of the position of each atom or molecule growth fully when the material preparation by people's design.

Example 1: " nano metal one insulating barrier one nano-silicon (being called for short nanometer MIS) Schottky barrier structure ".

Nano-silicon (nc-si) has a series of special performances, and as the room-temperature conductivity height, doping efficiency is good, and light, thermal stability are good, and light absorpting ability is strong etc., helps using in device.Present production technology is comparative maturity also, generally can utilize the PECVD deposition system, uses highly diluted silane to be reactant gas source, has the nc-si:H film growth of the strong nearly chemical balance attitude of [H] basic corrosiveness.The method for preparing nanometer metallic film also has multiple, as using vaporization condensation process, and ion sputtering method, low temperature plasma method, induced with laser method vapor deposition method, plasma enhanced chemical vapor deposition method or the like.

Shown in the accompanying drawing 1 for being the structure of the nanometer MIS Schottky barrier solar cell of substrate with glass.

Example 2, the oar material of after spraying on the semiconductor material layer with depletion layer built-in field is evenly mixed by ultrafine dust metal powder that quantitatively respectively accounts for 50% same size and semiconductor powder, making, form thin layer, behind oven dry, the sintering, spray one deck insulation antireflection anti-reflection film more thereon, the selection difference of size range has the paster that can absorb luminous energy or microwave energy and convert electric energy to and make described in then can be according to the present invention.The part surface internal organs of this paster is looked enlarged diagram, as shown in Figure 2.

Claims

1, a kind of light (or microwave)-electricity conversion structure of composite membrane.It is characterized in that have the semiconductor material layer that can play a part to separate and collect electronics above have the thin layer of ultrafine dust metal.The size range of said ultrafine dust, during as opto-electronic conversion, must be for (annotate: nanometer is a kind of tiny length unit, 1 nanometer=10 between 1 nanometer to 300 nanometer ^-9Rice); When absorbing microwave energy and convert electric energy to, must be for about about 300 nanometers to 1 micron.

2, a kind of light according to claim 1 (or microwave)-electricity conversion structure of composite membrane, said thin layer is by the metal of the ultrafine dust of the size range described in the claim 1 or semi-conductive monocrystalline, crystallite, nanocrystalline or amorphous material is formed, no matter whether its shape is regular with arrangement, and no matter whether simple metal or metal multilayer film, and comprise:

A, be the metal net shaped film of ultrafine dust that close grid type or close some type distribute, in the mesh of this reticulated film, can accommodate semi-conducting material or other material;

Said reticulated film also can be made of semi-conducting material among b, a, can accommodate the ultrafine dust metal material in the mesh of this reticulated film.Perhaps with the different semi-conductive ultrafine dust material of bandwidth of the semi-conducting material that constitutes this reticulated film.

3, according to claim 1,2 described a kind of light (or microwave)-electricity conversion structure of composite membrane.Its characteristics of carrying out light (or microwave)-electric transfer process are the small-size effects of having utilized ultrafine dust, in the time satisfying the resonance absorption condition, produce excited electron, separate by the semiconductor material layer described in the claim 1 then and collect bottom electrode light (or microwave) electromagnetic wave characteristics wavelength.