CONFIDENTIAL

AlN template on Sapphirefor Deep UV LEDContents•

Growth Method : HVPE•

Basic Properties of as grown AlN templates•

Improvement of surface morphology : CMP Process•

Regrowth Results•

Specifications of AlN templates

June 2018
LumiGNtech Co., Ltd.

1❖ Growth Method : HVPECONFIDENTIAL◆ Hydride Vapor Phase Epitaxy : 3 pcs x 2 inch wafer ( Usually Sapphire )◆ Maximum growth temperature : 1150℃◆ Crack free AlN layer thickness : typical ~ 2.0㎛ (maximum ~ 3.0 ㎛)

2❖ Basic Properties : As grown AlN template

CONFIDENTIAL◆ FWHM of X-ray Rocking Curve , Optical tramsmission at Deep UV Range◆ Surface morphology : Should be improved for Epi-Ready•

FWHM of X-racy rocking curve

FWHM(002) : 292 arcsec•

Optical Transmission•Surface morphology by OM(X200)•Surface morphology by AFM ( 20x20㎛)

FWHM(102) : 420 arcsec

Ra =7.227nm3

❖ Improvement of Surface morphology

CONFIDENTIAL◆ Epi-Ready surface by introduction of Chemical Mechanical Polishing Process

As Grown surface•After CMP surface

Surface morphology by OM(X200)

CMPProcess•

Surface morphology by AFM ( 20x20㎛)
Ra =7.227nm

Ra =0.223nm

4❖ AlN on Patterned Sapphire Substrate

CONFIDENTIAL◆ AlN on Cylindrical PSS••

FWHM of X-ray rocking curve
FWHM(002) : 428 arcsec

View of Cross-Section

FWHM(102) : 530 arcsec

3000003500

Intensity (a.u.)

Intensity (a.u.)

3000

200000100000

2500
2000
1500
1000
500

0
17.0

17.5

18.0

18.5

19.0

Omega (degree)

•0
24.0

24.5

25.0

25.5

26.0

Omega (degree)Surface morphology by AFM ( 20x20㎛)
Ra = 33.68 nm

Ra =0.26nm

CMPProcess

As Grown surface

After CMP surface5❖ AlGaN Regrowth on AlN template

CONFIDENTIAL◆ AlGaN(Al: 50%) on AlN template by conventional MOCVD ( Veecon D300 )AlN template

120

AlGaN on AlN template

FWHM(102) of AlGaN layer : 500 arcsec
Intensity (cps)Transmission of AlGaN template

100-17 (arcsec), 2817 (cps)
3000

80

2500

60

2000

500 (arcsec)

1500

40
Bottom

20Center

1000

Top

500

0190

290

390

490

590

0-8000-6000-4000-200002000

4000

6000

8000

66Omega (s)6❖ AlGaN on AlN template (HVPE vs MOCVD)CONFIDENTIAL◆ XRD of AlGaN (Al: 50%) on AlN template ( HVPE vs MOCVD )1 μm-thick –Al0.5GaN(1070`C, MOCVD)AlN/Al0.5GaN SLs

1 μm-thick -AlN

SapphireXRD Intensity (a.u.)4000
AlGaN onon
HVPE-AlN
template
AlGaN04
HVPE-AlN
Template
AlGaN04
MOCVD-AlN
Template
AlGaN onon
MOCVD-AlN
template

3000

AlN template

2000

1000

Al0.5GaN
Al0.48GaN

017.6

17.7

17.8

17.9

18.0

18.1

18.2

18.3

Omega-2Theta (degree)
4000
AlGaN onon
HVPE-AlN
template
AlGaN08
HVPE-AlN
Template
AlGaN08
HVPE-AlNtemplate
Template
AlGaN onon
MOCVD-AlN

1 μm-thick–Al0.5GaN(1070`C, MOCVD)
0.2 μm-thick–Al0.75GaN(1070`C, MOCVD)
1 μm-thick-AlN

SapphireXRD Intensity (a.u.)

Al0.495GaN
3000

AlN template
Al0.54GaN

2000

1000

Al0.68GaN
017.6

17.7

17.8

17.9

18.0

18.1

18.2

Omega-2Theta (degree)

18.3

7

❖ MQW on AlN template (HVPE vs MOCVD)CONFIDENTIAL◆ MQW on AlN template (HVPE vs MOCVD) : Strain Effect ?

PL Intensity (a.u.)

60000
50000

MQW on HVPE-AlN template
MQW on MOCVD-AlN template

AlGaN MQWs

288.7 nm

1 μm-thick–Al0.5GaN(1070`C, MOCVD)
0.2 μm-thick–Al0.75GaN(1070`C, MOCVD)

40000
30000

1 μm-thick-AlN

20000

319.5 nm

10000
0200

(23/77 Å)x8 periods

Sapphire
300

400

500

600700

Wavelength (nm)8❖ UV LED EPI regrowth

CONFIDENTIAL◆ UV LED EPI Regrowth on Lumi’s AlN template•Surface morphology by OM(X200)•Vf of 275 nm UV LED epi-wafer

UV-C epi
Growth9