WO2000021143A1 - Radiation emitting semiconductor chip - Google Patents

Radiation emitting semiconductor chip Download PDF

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Publication number
WO2000021143A1
WO2000021143A1 PCT/DE1999/003211 DE9903211W WO0021143A1 WO 2000021143 A1 WO2000021143 A1 WO 2000021143A1 DE 9903211 W DE9903211 W DE 9903211W WO 0021143 A1 WO0021143 A1 WO 0021143A1
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WO
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Application
Patent type
Prior art keywords
active layer
semiconductor chip
gan
gainn
radiation
Prior art date
Application number
PCT/DE1999/003211
Other languages
German (de)
French (fr)
Inventor
Volker HÄRLE
Berthold Hahn
Andreas Hangleiter
Original Assignee
Osram Opto Semiconductors Gmbh & Co. Ohg
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    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/26Materials of the light emitting region
    • H01L33/30Materials of the light emitting region containing only elements of group III and group V of the periodic system
    • H01L33/32Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y20/00Nanooptics, e.g. quantum optics or photonic crystals
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/04Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a quantum effect structure or superlattice, e.g. tunnel junction
    • H01L33/06Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a quantum effect structure or superlattice, e.g. tunnel junction within the light emitting region, e.g. quantum confinement structure or tunnel barrier
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/005Processes
    • H01L33/0062Processes for devices with an active region comprising only III-V compounds
    • H01L33/0066Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound
    • H01L33/007Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound comprising nitride compounds
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/26Materials of the light emitting region
    • H01L33/30Materials of the light emitting region containing only elements of group III and group V of the periodic system
    • H01L33/32Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen
    • H01L33/325Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen characterised by the doping materials
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES USING STIMULATED EMISSION
    • H01S5/00Semiconductor lasers
    • H01S5/02Structural details or components not essential to laser action
    • H01S5/0206Substrates, e.g. growth, shape, material, removal or bonding
    • H01S5/021Silicon based substrates
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES USING STIMULATED EMISSION
    • H01S5/00Semiconductor lasers
    • H01S5/30Structure or shape of the active region; Materials used for the active region
    • H01S5/305Structure or shape of the active region; Materials used for the active region characterised by the doping materials used in the laser structure
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES USING STIMULATED EMISSION
    • H01S5/00Semiconductor lasers
    • H01S5/30Structure or shape of the active region; Materials used for the active region
    • H01S5/34Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers]
    • H01S5/3407Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers] characterised by special barrier layers
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES USING STIMULATED EMISSION
    • H01S5/00Semiconductor lasers
    • H01S5/30Structure or shape of the active region; Materials used for the active region
    • H01S5/34Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers]
    • H01S5/3425Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers] comprising couples wells or superlattices
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES USING STIMULATED EMISSION
    • H01S5/00Semiconductor lasers
    • H01S5/30Structure or shape of the active region; Materials used for the active region
    • H01S5/34Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers]
    • H01S5/343Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers] in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser
    • H01S5/34333Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers] in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

A semiconductor chip, especially a GaN/GaInN based chip, that emits radiation, whereby the active layer has a multi quantum wave structure. The active layer has very thin quantum films (maximum thickness: 3 nm) and/or electro-conductive doped barrier layers and/or quantum films. The wavelengths of the emitted radiation is substantially independent of changes in the intensity of the current through the chip.

Description

description

Radiation-emitting semiconductor chip

The invention relates to a radiation-emitting semiconductor chip, in particular based on GaN / GaInN, wherein the active layer has a single or multiple quantum well structure, and in particular UV, blue - light or green light-emitting semiconductor chips.

The active layer comprises at a single quantum well typically two barrier layers and between these quantum film, and in a multiple quantum well typically x quantum wells and x + 1 barrier layers (where x> l), in the embedded quantum films are. Single and multiple quantum well structures are known and are not explained therefore at this point.

The wavelength of the radiation emitted by such known light emitting semiconductor chips (LED (Light

Emitting Diode) chip) is strongly dependent on the level of the operating current.

The reason for this may be the one in-segregation in the quantum well region and may be on the other piezoelectric fields, which are caused by internal tensions in the chip. An application of electrical voltage to the chip in the forward direction leads to a scanning of the internal fields and with increasing current through the chip to a wavelength shift of the emitted radiation to shorter wavelengths. The greater is the wavelength of the emitted radiation, the stronger this effect is.

The object of the invention is to develop a semiconductor chip of the type mentioned, in which the wavelength of the emitted radiation is substantially independent to changes in current through the chip.

This object is achieved by a semiconductor chip having the features of claim 1, 4, 5 or. 6 In such a semiconductor chip, the piezoelectric fields are kept small and / or very largely compensated by the installation of additional internal fields.

The former is achieved with a semiconductor chip of the type mentioned, in which the active layer has quantum thin films with a thickness of <3 nm.

A particularly preferred, schematically illustrated in Figure 1 embodiment, this is a

Semiconductor chip having an active layer 4, which has a GaN / GaInN multiple quantum well structure in which 3.5 GaInN quantum wells with a thickness of <3 nm disposed between GaN barrier layers and the fabricated on a SiC substrate 1, wherein further layers, in particular a buffer layer 2, located between the substrate 1 and the active layer 4 still.

The second option is achieved with a semiconductor chip of the type mentioned, wherein the barrier layers 3,5 and / or the quantum wells are electrically conductively doped. The doping is designed to present fields, so that they are compensated for. It is based on the strain in the active layer.

An optimum compensation of the piezo fields is achieved by a high doping of the active layer. Thus, the piezoelectric fields are virtually shorted. Thus, the carrier densities also occur during subsequent operation are anticipated. Technically, this is possible, for example by high n-doping in the region of the active zone. To the highest possible ratio p / (p + n) to achieve high p-type doping is needed.

The charge carrier densities needed for compensation of the internal fields are greater than 10 19 cιrf. 3 They are obtained by doping the quantum well region or by remote doping of barrier layers.

Alternatively, the barrier layers can be doped bipolar. An effective compensation can be achieved by acceptors and donors directly on the quantum well. The charge carrier densities greater than 10 19 cιrf. 3 Advantageously, for effective doping p- above the quantum well and heavily n-doped under the quantum well. The piezoelectric fields are canceled by the caused by the ionized donors and acceptors fields.

A particularly preferred embodiment is a semiconductor chip with an active layer having a GaN / GalnN- multiple quantum well structure in which between the GaN

Barrier layers GaInN quantum wells are arranged and which is formed on a SiC substrate, and in which, may be located between the substrate and the active layer, further layers, in particular a buffer layer, the GaN barrier layers and / or the GaInN -

Quantum films electrically conductively doped, that is n- or p- doped. The doping is based on the strain, not the structure, ie, for example on a n- or p-doped buffer layer.

In a third solution possibility of a relaxed semiconductor layer is disposed between the substrate and the active layer having the same lattice constant as the lattice constant in the quantum well.

A particularly preferred, schematically illustrated in Figure 2 embodiment this is a semiconductor chip having an active layer 4, which has a GaN / GaInN multiple quantum well structure in which 3.5 GaInN Quantenfil e are arranged between GaN barrier layers and the on a SiC substrate 1 is manufactured, said active between the substrate 1 and the

Layer 4 is a relaxed InGaAlN film 6 having the same lattice constant as that of the quantum well. The barrier layers 5, 6 are made of AlGaInN.

The structures shown above may be applied to all the GaInN / GaN-based LEDs, as well as for all the structures that contain substantial internal Verspannungsfeider.

Claims

claims
1. radiation-emitting semiconductor chip, in particular based on GaN / GaInN, in which an active layer (4) has a single or multiple quantum well structure, characterized in that the active layer quantum wells with a thickness of <3 nm.
2. radiation-emitting semiconductor chip according to claim 1, characterized in that the active layer (4) has a GaN / GaInN Multiquantenwell- structure in which between the GaN barrier layers (3,5) GaInN Quantenfil e are disposed with a thickness of <3 nm and which is prepared via an SiC substrate (1).
3. radiation-emitting semiconductor chip according to claim 2, characterized in that the quantum wells and / or the barrier layers are electrically conductive doped.
4 radiation-emitting semiconductor chip, in particular based on GaN / GaInN, in which an active layer (4) has a single or multiple quantum well structure, characterized in that the quantum films of the single- or multi-quantum well structure of electrically conductive are doped.
5. radiation-emitting semiconductor chip, in particular based on GaN / GaInN, wherein the active layer (4) has a single or multiple quantum well structure interposed between barrier layers (3,5) is arranged, characterized in that the quantum wells and / or the barrier layers are electrically conductive doped.
6. radiation-emitting semiconductor chip, in particular based on GaN / GaInN, in which an active layer (4) is a single or multiple quantum well structure, characterized in that between a substrate (1) and the active layer (4) arranged a relaxed semiconductor layer having the same lattice constant as the lattice constant in the quantum well.
7. radiation-emitting semiconductor chip according to claim 6, characterized in that the active layer (4) has a GaN / GaInN Multiquantenwell- structure in the intermediate GaN barrier layers (3,5) GaInN quantum wells disposed on a SiC substrate (1) is produced, wherein there is a relaxed InGaAlN layer between the substrate (1) and the active layer.
PCT/DE1999/003211 1998-10-05 1999-10-05 Radiation emitting semiconductor chip WO2000021143A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE19845748 1998-10-05
DE19845748.0 1998-10-05

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001092428A1 (en) * 2000-06-02 2001-12-06 Erhard Kohn Heterostructure with rear-face donor doping
WO2002097904A2 (en) * 2001-05-30 2002-12-05 Cree, Inc. Group iii nitride based light emitting diode structures with a quantum well and superlattice
WO2003012877A2 (en) * 2001-07-20 2003-02-13 Erhard Kohn Field effect transistor
US7692182B2 (en) 2001-05-30 2010-04-06 Cree, Inc. Group III nitride based quantum well light emitting device structures with an indium containing capping structure
WO2011098799A2 (en) 2010-02-10 2011-08-18 Pulmagen Therapeutics (Inflammation) Limited Respiratory disease treatment
US8772757B2 (en) 2005-05-27 2014-07-08 Cree, Inc. Deep ultraviolet light emitting devices and methods of fabricating deep ultraviolet light emitting devices
US9012937B2 (en) 2007-10-10 2015-04-21 Cree, Inc. Multiple conversion material light emitting diode package and method of fabricating same
US9041139B2 (en) 2007-01-19 2015-05-26 Cree, Inc. Low voltage diode with reduced parasitic resistance and method for fabricating
US20170213868A1 (en) * 2014-04-01 2017-07-27 Centre National De La Recherche Scientifique Semiconducting pixel, matrix of such pixels, semiconducting structure for the production of such pixels and their methods of fabrication

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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7352008B2 (en) * 2000-06-02 2008-04-01 Microgan Gmbh Heterostructure with rear-face donor doping
WO2001092428A3 (en) * 2000-06-02 2002-05-30 Erhard Kohn Heterostructure with rear-face donor doping
WO2001092428A1 (en) * 2000-06-02 2001-12-06 Erhard Kohn Heterostructure with rear-face donor doping
US9112083B2 (en) 2001-05-30 2015-08-18 Cree, Inc. Group III nitride based light emitting diode structures with a quantum well and superlattice, group III nitride based quantum well structures and group III nitride based superlattice structures
WO2002097904A3 (en) * 2001-05-30 2003-02-20 Cree Inc Group iii nitride based light emitting diode structures with a quantum well and superlattice
US6958497B2 (en) 2001-05-30 2005-10-25 Cree, Inc. Group III nitride based light emitting diode structures with a quantum well and superlattice, group III nitride based quantum well structures and group III nitride based superlattice structures
US7312474B2 (en) 2001-05-30 2007-12-25 Cree, Inc. Group III nitride based superlattice structures
WO2002097904A2 (en) * 2001-05-30 2002-12-05 Cree, Inc. Group iii nitride based light emitting diode structures with a quantum well and superlattice
US7692182B2 (en) 2001-05-30 2010-04-06 Cree, Inc. Group III nitride based quantum well light emitting device structures with an indium containing capping structure
US9054253B2 (en) 2001-05-30 2015-06-09 Cree, Inc. Group III nitride based quantum well light emitting device structures with an indium containing capping structure
WO2003012877A3 (en) * 2001-07-20 2003-09-18 Erhard Kohn Field effect transistor
WO2003012877A2 (en) * 2001-07-20 2003-02-13 Erhard Kohn Field effect transistor
US8772757B2 (en) 2005-05-27 2014-07-08 Cree, Inc. Deep ultraviolet light emitting devices and methods of fabricating deep ultraviolet light emitting devices
US9041139B2 (en) 2007-01-19 2015-05-26 Cree, Inc. Low voltage diode with reduced parasitic resistance and method for fabricating
US9012937B2 (en) 2007-10-10 2015-04-21 Cree, Inc. Multiple conversion material light emitting diode package and method of fabricating same
WO2011098799A2 (en) 2010-02-10 2011-08-18 Pulmagen Therapeutics (Inflammation) Limited Respiratory disease treatment
US20170213868A1 (en) * 2014-04-01 2017-07-27 Centre National De La Recherche Scientifique Semiconducting pixel, matrix of such pixels, semiconducting structure for the production of such pixels and their methods of fabrication

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