Use in electrical and electronic equipment

• Author: Clemm, Christan; Löw, Clara; Baron, Yifaat; Moch, Katja; Möller, Martin; Köhler, Andreas R; Gensch, Carl-Otto; Deubzer, Otmar
• Pages: 13-21

RoHS Annex II Dossier, final

Indium phosphide

13

3 USE IN ELECTRICAL AND ELECTRONIC EQUIPMENT

Indium phosphide is employed in a wide variety of devices, products, and applications. Due to its

semiconductor and photovoltaic properties, indium phosphide is used in a wide array of applications

in optoelectronic devices, displays, high-speed electronics and photovoltaics. Typical applications of

InP include e.g.:13

• Lasers, photo detectors and modulators used for global telecommunication networks;

• Spectroscopic analysers and LiDAR (Light Detection And Ranging) applications;

• High Electron Mobility Transistors (HEMT) and Heterostructure Bipolar Transistors (HBT) for high-

speed electronic devices;

• Semiconductor quantum dots (QD) as a colour converting component of liquid crystal display

backlit devices;

• Substrate for photovoltaic cells.

3.1 Function of the substance

As compared to other semiconductor materials such as silicon and gallium arsenide (GaAs), indium

phosphide is generally characterised by superior electrical and thermal properties, higher electron

mobility, higher frequency as well as higher thermal conductivity.

In optoelectronic appliances, InP-based active material produces light emission, detection, or

modulation at wavelengths compatible with low dispersion or low loss in optical fibres, which enables

much higher data rates (for a given distance) or much longer distances (for the same data rate) than

can be achieved with other materials, like e.g. GaAs. Consequentially, the wafers have low power

consumption and a low noise performance.14

With these functionalities, indium phosphide is considered to be the enabling semiconductor material

for high power and/or high frequency performance electronic components and for various

functionalities of optoelectronic devices. In these devices InP, as the gain medium15 of generating

infrared light, is responsible for the emission wavelength of laser chips and the detection wavelength

of the photo-diodes at 1.30 m or 1.50 m ranges. The wavelength windows are determined by the

minimum absorption windows of silica which is the key material of optical fibres used in

telecommunications networks.16 17

13 References are included in sections 2.1 and 2.2

14 T&M Coalition (2018), Contribution of Test / Measurement Coalition submitted on 15.06.2018 during the stakeholder

consultation conducted from 20 April 2018 to 15 June 2018 by Oeko-Institut in the course of the study to support the

review of the list of restricted substances and to assess a new exemption request under RoHS 2 (Pack 15);

http://rohs.exemptions.oeko.info/fileadmin/user_upload/RoHS_Pack_15/1st_Consultation_Contributions/Contribution

_TMC_7_Substances_response_20180615_fin.pdf, last viewed 20.12.2018

15 A gain medium is a medium which can amplify the power of light (typically in the form of a light beam), which is needed

in a laser in order to compensate for the resonator losses.

16 Coherent (2018), Contribution of Coherent submitted on 12.06.2018 during the stakeholder consultation conducted

from 20 April 2018 to 15 June 2018 by Oeko-Institut in the course of the study to support the review of the list of

restricted substances and to assess a new exemption request under RoHS 2 (Pack 15);

http://rohs.exemptions.oeko.info/fileadmin/user_upload/RoHS_Pack_15/1st_Consultation_Contributions/Contribution

_Coherent_Indium_phosphide_Stakeholder_Response_20180612.pdf, last viewed 20.12.2018;

17 3SPT (2018), Contribution of 3SPT submitted during the stakeholder consultation conducted from 20 April 2018 to 15

June 2018 by Oeko-Institut in the course of the study to support the review of the list of restricted substances and to

assess a new exemption request under RoHS 2 (Pack 15);

http://rohs.exemptions.oeko.info/fileadmin/user_upload/RoHS_Pack_15/1st_Consultation_Contributions/Contribution

_3SPT_Technologies_InP_1st_Stakeholder_Consultation_InP_3SPT_Participation.pdf, last viewed 20.12.2018