Si(111)转移至嵌入式宽p电极Cu基座的GaN LED垂直结构性能提升

研究论文

199 浏览量更新于2024-08-26 收藏 838KB PDF 举报

身份认证购VIP最低享 7 折!

30元优惠券

资源详情

资源推荐

Chin. Phys. B Vol. 24, No. 3 (2015) 038503

Performance improvement of GaN-based light-emitting diodes

transferred from Si (111) substrate onto electroplating

Cu submount with embedded wide p-electrodes

∗

Liu Ming-Gang(柳铭岗)

†

, Wang Yun-Qian(王云茜)

†

, Yang Yi-Bin(杨亿斌)

†

Lin Xiu-Qi(林秀其), Xiang Peng(向鹏), Chen Wei-Jie(陈伟杰), Han Xiao-Biao(韩小标),

Zang Wen-Jie(臧文杰), Liao Qiang(廖强), Lin Jia-Li(林佳利), Luo Hui(罗慧),

Wu Zhi-Sheng(吴志盛), Liu Yang(刘扬), and Zhang Bai-Jun(张佰君)

‡

State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China

(Received 30 July 2014; revised manuscript received 20 October 2014; published online 30 January 2015)

Crack-free GaN/InGaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) are transferred from Si sub-

strate onto electroplating Cu submount with embedded wide p-electrodes. The vertical-conducting n-side-up conﬁguration

of the LED is achieved by using the through-hole structure. The widened embedded p-electrode covers almost the whole

transparent conductive layer (TCL), which could not be applied in the conventional p-side-up LEDs due to the electrode-

shading effect. Therefore, the widened p-electrode improves the current spreading property and the uniformity of lumi-

nescence. The working voltage and series resistance are thereby reduced. The light output of embedded wide p-electrode

LEDs on Cu is enhanced by 147% at a driving current of 350 mA, in comparison to conventional LEDs on Si.

Keywords: light-emitting diodes, embedded wide p-electrodes, Si substrate, electroplating Cu submount

PACS: 85.60.Jb, 61.72.uj, 82.45.Qr DOI: 10.1088/1674-1056/24/3/038503

1. Introduction

Over the last two decades, GaN-based LEDs on sap-

phire and SiC substrates have been applied in many ﬁelds,

such as displays, trafﬁc signals, automotive lighting, and back-

lights. This is due to the rapid development of the LED

technologies.

[1–13]

Speciﬁcally, the progress in achieving in-

ternal quantum efﬁciency improvement and radiative efﬁ-

ciency enhancement,

[2,14,15]

hole transport improvement and

efﬁciency-droop suppression in the LEDs leading to practical

applications,

[16–21]

and the deep understanding of Auger pro-

cess in nitride LEDs

[22,23]

have been the driving force in ad-

vancing the technologies. In order to further reduce the cost of

LEDs and replace traditional lamps, the LEDs on Si substrates

have attracted considerable interest, owing to many good prop-

erties of Si such as low cost, large scale, high quality, low hard-

ness, and good thermal conductivity and electrical conduction.

Although GaN-based LEDs on Si substrates have been ex-

tensively studied and their performances have been improved

greatly, the volume production remains difﬁcult mainly due

to the stress problems between GaN and Si substrate and the

optical absorption by the opaque Si substrate. The stress prob-

lems can be partially solved by using graded AlGaN buffer

layers

[24,25]

and AlN/GaN superlattices.

[26,27]

In order to im-

prove the light efﬁciency, inserting a distributed Bragg reﬂec-

tor (DBR) between the active layer of LED and the substrate is

an easy and effective method for reducing the absorption of Si

substrate.

[28–30]

However, because of the tensile stress and the

crack formation, only a few pairs of DBRs are available to be

deposited on Si substrates in the premise of crackfree, which

results in lower reﬂectivity. Moreover, only a given light po-

larization impinging near the normal direction to the DBR

structure can be effectively reﬂected.

[31]

In addition, DBRs are

usually applied in conventional p-side-up LEDs, which cannot

eliminate the shadow effect by p-electrodes.

[32]

Therefore, the

Si substrate transferring technique

[33–40]

is mainly adopted to

eliminate the absorption of Si substrates and shadow effect,

by inserting a metallic reﬂector. For instance, in our pre-

vious work,

[40]

we presented the embedded electrode LEDs

(EE-LEDs) transferred from Si substrate onto Cu submount,

which enhances the light output by 122%. However, since the

p-electrode is much narrower than the TCL and the thin TCL

presents lateral resistance, it leads to current crowding near the

p-electrode,

[40,41]

which would also aggravates the shadow ef-

fect in the conventional p-side-up LEDs. This current crowd-

ing adversely affects the uniformity and stability of the light

emission.

[42]

Moreover, the current crowding also causes op-

tical saturation, decrease in the efﬁciency of light generation,

and degradation in the reliability of LEDs, due to the high-

electrical carrier density in a localized area of the device.

[43]

∗

Project supported by the National Natural Science Foundation of China (Grant Nos. 61274039 and 51177175), the National Basic Research Program of China

(Grant Nos. 2010CB923201 and 2011CB301903), the Ph.D. Program Foundation of Ministry of Education of China (Grant No. 20110171110021), and the

Foundation of the Key Technologies R&D Program of Guangdong Province, China (Grant No. 2010A081002005).

†

These authors contributed equally to this work.

‡

Corresponding author. E-mail: zhbaij@mail.sysu.edu.cn

038503-1

下载后可阅读完整内容，剩余5页未读，立即下载

weixin_38734276

粉丝: 11
资源: 902

Si(111)转移至嵌入式宽p电极Cu基座的GaN LED垂直结构性能提升

使用TiO2 / SiO2-Al全向反射器增强从Si（111）衬底转移到电镀Cu基座上的GaN基发光二极管

GaN基LED芯片发光效率提升研究.pdf

利用汇编与接口程序实现8255A的C口连接8只发光二极管，通过置位控制字循环点亮发光二极管

嵌入式集成芯片的物理原理

汇编语言编程实现 要求8个发光二极管按12 34 56 78 12的顺序，每隔一段时间周而复始逐个点亮

stm32 si4703

si1000 si4432

已知（1）Si PIN光电二极管，量子效率η=0.7，波长λ=850nm，（2）Ge光电二极管，量子效率η=0.4，波长λ=1600nm，计算它们的响应度

silu激活函数改进

有关半导体照明microLED发表在Top期刊中的文章，要求在2020年后发表的，至少30篇，并用中文简单介绍一下它们的内容

有关半导体照明microLED发表在Top期刊中的期刊，要求在2020年后发表的，至少20篇，并用中文简单介绍一下它们的内容

SI8380P的原理和固态继电器的原理

swish和silu激活函数

验证siso收发端性能

Hardswish激活函数相较于Silu激活函数的优点

LTE频分多址技术，验证SISO、SIMO收发端性能

二极管击穿电压与那些因素有关

最新资源

汇编语言编程实现要求8个发光二极管按12 34 56 78 12的顺序，每隔一段时间周而复始逐个点亮