CN102447024B

CN102447024B - A kind of nanoscale PSS substrate preparation method

Info

Publication number: CN102447024B
Application number: CN201110330648.1A
Authority: CN
Inventors: 周武; 罗红波; 张建宝; 刘榕
Original assignee: HC Semitek Corp
Current assignee: HC Semitek Zhejiang Co Ltd
Priority date: 2011-10-27
Filing date: 2011-10-27
Publication date: 2016-06-01
Anticipated expiration: 2031-10-27
Also published as: CN102447024A

Abstract

Disclosure one nanoscale PSS substrate preparation method, on a sapphire substrate one layer of SiO of deposition₂Film, at SiO₂Film deposition layer of metal Al, with a kind of weakly alkaline chemical solution, at SiO₂Film surface generates uniform aluminum oxide nano-particle, removes the SiO not blocked by aluminum oxide with dry etching₂Film, so by uniform aluminum oxide nano-particle Graphic transitions to SiO₂Rete, is then placed in sulphuric acid and the corrosion in phosphoric acid mixed solution of high temperature, transfers in Sapphire Substrate by the SiO2 grain pattern of even shape again, finally remove SiO2 film with HF acid, thus forming nanoscale PSS substrate. This invention can improve the outer quantum effect of LED chip, and cost of manufacture is low, produces high efficiency.

Description

A kind of nanoscale PSS substrate preparation method

Technical field

The present invention relates to a kind of LED substrate manufacture method, especially a kind of nanoscale PSS substrate preparation method.

Background technology

Light emitting diode (LED) is a kind of electro-optic conversion, energy-efficient, environmental protection, the advantages such as life-span length, indicate in traffic, indoor outer total colouring, the aspects such as LCD TV backlight source have a wide range of applications, semiconductor solid lighting can be realized particularly with LED, it is expected to become a new generation's light source and enters huge numbers of families, the mankind are caused to illuminate the revolution in history, the blue-light LED chip of Sapphire Substrate growing gallium nitride extension wherein applies yellow fluorescent powder, blue-light excited fluorescent material sends gold-tinted, blue light and yellow light mix obtain white light, thus obtaining white light with blue-ray LED. backing material that the LED of epitaxy of gallium nitride adopts is common two kinds, i.e. sapphire and carborundum, carborundum machining property is poor, expensive and patent aspect problem makes it apply to be limited, therefore the substrate being currently used in GaN epitaxial growth is mainly sapphire, epitaxial layer of gallium nitride is quite big with sapphire lattice mismatch, residualinternal stress is bigger, so growing gallium nitride easily causes substantial amounts of defect on sapphire, and these defects are substantially reduced luminescent device luminous efficiency, there is the difference of bigger refractive index between GaN and air, light shooting angle is less, and significant portion is totally reflected back to inside LED chip simultaneously, reduces the extraction efficiency of light, increases heat radiation difficulty, affects the reliability of LED component. employing nanoscale PSS substrate technology can be substantially reduced the density of the dislocation of nitride material, the residualinternal stress produced when relaxing epitaxial growth, improves internal quantum efficiency, and light extraction efficiency is substantially improved.

Realize nanoscale PSS substrate technology at present mainly to adopt: electron beam lithography, nano imprint lithography, polymer light lithography; Above technology processed complex, cost are high.

Summary of the invention

It is an object of the invention to provide a kind of nanoscale PSS substrate preparation method, this manufacture method is simple and easy, quick, low cost, and photon extraction efficiency is high, improving product yield.

The technical scheme is that a kind of nanoscale PSS substrate preparation method, preparation process is as follows:

A, Sapphire Substrate deposit one layer of SiO₂Film: deposit one layer of SiO by PECVD device in Sapphire Substrate₂Film, thickness about 2000��5000 angstroms.

B, at SiO₂Film evaporates layer of metal aluminum: at SiO₂Film evaporates layer of metal aluminum, thickness about 500��1000 angstroms.

C, by step b evaporate layer of metal aluminum substrate be immersed in weakly alkaline chemical solution, carry out chemical action, SiO₂Film surface leaves uniform aluminum oxide nano-particle: step b evaporates the substrate of layer of metal aluminum and is immersed in the chemical solution of 0.5��2% alkalescence, soaks 2��5 minutes, SiO₂Film surface generates the aluminum oxide nano-particle of uniform 50��300 angstroms.

D, after step c chemical action, then dry etching falls the SiO failing to be blocked by aluminum oxide nano-particle₂Film, by al oxide granule Graphic transitions to SiO₂Rete, forms the SiO of nanometer shape₂Granule: d, after step c chemical action, adopts RIE equipment to etch away the SiO failing to be blocked by aluminum oxide nano-particle₂Film, by the al oxide granule Graphic transitions of uniform nanometer of shape to SiO₂Rete; , form the SiO of nanometer shape₂Granule. The parameter that RIE equipment adopts is: CF4 flow 30��60sccm; Reaction pressure 20��100mTorr; Power 300��500W, etch period 10��30 minutes.

E, the sulphuric acid placing into high temperature after Step d and phosphoric acid mixed solution erode not by SiO₂The blue precious substrate that granule blocks: (e) places into sulphuric acid and the phosphoric acid mixed solution H of 230��350 DEG C of temperature after Step d₂SO₄:H₃PO₄=3:1 corrodes about 10��30 minutes, erode not by SiO₂The blue precious substrate that granule blocks.

F, after step e, remove SiO with HF acid₂Mask, forms nanoscale PSS substrate: with HF acid corrosion 10��30 minutes after step e, remove SiO₂Mask, forms nanoscale PSS substrate.

It is an advantage of the current invention that: its processing procedure is relative to conventional PSS technology, and its technology requires relatively low, and etching speed is fast; Exempting and fall expensive lithographic equipment, processing cost reduction is a lot; And relative to non-PSS processing procedure, the pit pattern that this processing procedure is formed on sapphire is conducive to growing high-quality epitaxial layer of gallium nitride, be conducive to improving outer quantum effect; The light that LED inspires simultaneously reflects at these pit pattern places, can form scattering light, is conducive to increasing light extraction efficiency.

Accompanying drawing explanation

Fig. 1 is one nanoscale PSS substrate preparation method structural representation of the present invention

P1 sapphire, P2 SiO2 film, P3 aluminium lamination, A ~ G processing procedure corresponding steps substrat structure pattern.

Detailed description of the invention

Fig. 1 showing, the present invention forms nanoscale PSS substrate implementing procedure in emitting components;

Step a: deposit one layer of SiO2 film in Sapphire Substrate;

Step b: evaporate layer of metal aluminum on SiO2 film;

Step c: the substrate that step b evaporates layer of metal aluminum is immersed in weakly alkaline organic chemistry solution, carries out chemical action, SiO2 film surface generates uniform aluminum oxide nano-particle;

Step d: after step c chemical action, then dry etching falls the SiO2 film failing to be blocked by aluminium salt, by the al oxide granule Graphic transitions of uniform nanometer of shape to SiO2 rete; , form the SiO2 granule of nanometer shape;

Step e: place into after Step d in the sulphuric acid of high temperature and phosphoric acid mixed solution and erode the blue precious substrate not blocked by SiO2 granule;

Step f: remove SiO2 mask with HF acid after step e, form nanoscale PSS substrate.

Embodiment 1

First deposit one layer of SiO2 film, thickness about 2000��5000 angstroms by PECVD device on a sapphire substrate; Then on SiO2 film, evaporate layer of metal aluminum, thickness about 500��1000 angstroms; With organic chemistry solution alkalescence (0.5��2%), the substrate of metallic aluminium is soaked (2��5 minutes), SiO2 film surface generates the aluminum oxide nano-particle (50��300 angstroms) of uniform Conglobation type; Then with RIE equipment (parameter: CF4:30��60sccm; Reaction pressure: 20��100mTorr; Power: 300��500W, etch period: 10��30 minutes), compare with phosphoric acid mixed volume followed by sulphuric acid: 3:1; The mixed solution of temperature (230��350 DEG C) corrodes 10��30 minutes; Finally use HF acid corrosion SiO2 mask 10��30 minutes, form nanoscale PSS substrate.

Claims

1. a nanoscale PSS substrate preparation method, preparation process is as follows:

A () Sapphire Substrate deposits one layer of SiO₂Film;

B () is at SiO₂Film evaporates layer of metal aluminum;

C the substrate that step b evaporates layer of metal aluminum is immersed in weakly alkaline chemical solution by (), carry out chemical action, SiO₂Film surface stays uniform aluminum oxide nano-particle;

D () is after step c chemical action, then dry etching falls the SiO failing to be blocked by aluminum oxide nano-particle₂Film, by al oxide granule Graphic transitions to SiO₂Rete, forms the SiO of nanometer shape₂Granule;

E () places into after Step d in sulphuric acid and phosphoric acid mixed solution and erodes not by SiO₂The Sapphire Substrate that granule blocks;

F () removes SiO2 mask with HF acid after step e, form nanoscale PSS substrate.

2. nanoscale PSS substrate preparation method according to claim 1, it is characterised in that: (a) step Sapphire Substrate deposits one layer of SiO2 film, thickness 2000��5000 angstroms by PECVD device;

3. nanoscale PSS substrate preparation method according to claim 1, it is characterised in that: (b) step evaporates layer of metal aluminum, thickness 500��1000 angstroms on SiO2 film.

4. nanoscale PSS substrate preparation method according to claim 1, it is characterized in that: the substrate that step b evaporates layer of metal aluminum is immersed in the chemical solution of 0.5��2% alkalescence by (c) step, soak 2��5 minutes, SiO2 film surface generates the aluminum oxide nano-particle of uniform 50��300 angstroms.

5. nanoscale PSS substrate preparation method according to claim 1, it is characterized in that: (d) is after step c chemical action, re-use RIE equipment, etch away the SiO2 film failing to be blocked by aluminum oxide nano-particle, by the al oxide granule Graphic transitions of uniform nanometer of shape to SiO2 rete, form the SiO2 granule of nanometer shape. The working condition of RIE equipment is: CF4 flow 30��60sccm; Reaction pressure 20��100mTorr; Power 300��500W, etch period 10��30 minutes.

6. nanoscale PSS substrate preparation method according to claim 1, it is characterised in that: (e) places into sulphuric acid and the phosphoric acid mixed solution H of 230��350 DEG C of temperature after Step d₂SO₄:H₃PO₄=3:1 corrodes 10��30 minutes, erodes not by SiO₂The Sapphire Substrate that granule blocks.

7. nanoscale PSS substrate preparation method according to claim 1, it is characterised in that: (f) with HF acid corrosion 10��30 minutes, removes SiO after step e₂Mask, forms nanoscale PSS substrate.