Objective
The industrial objective of the HERO'S project is to deliver to the European market a commercial source of reliable InGaP/GaAs Heterojunction Bipolar Transistor (HBT) wafers. High reliability has still to be demonstrated for HBT devices working above 3GHz and up to 20GHz and devoted to power applications, which are the main market for HBTs. The project will also generate the know-how for on-wafer fast reliability assessments.
To realize this objective, the Consortium will develop HBT layers that will satisfy the high power and high frequency market needs:
- The reliability specification required by end-users typically is a mean-time-to failure (MTTF) of 10 6 hours at junction temperature Tj = 150ÐC and 30kA cm -2 for devices working up to 20GHz;
- Development of a testing equipment to give a first estimate of wafer reliability in few hours instead of months.
The main effort is devoted to optimisation of crystal growth conditions which merges the effort of a commercial supplier of MOCVD-grown wafers and of an epitaxy group of a R&D centre. The commercial supplier will focus his activity on growth optimisation while the R&D centre will explore new crystalline schemes for reliability improvement. A very strong, part of the project will be devoted to the material characterization (optical and electrical) with a special care to the hydrogen behaviour in HBT devices. which should give rise to hydrogen-free devices. The second part of HERO'S project will focus on electrical and reliability behaviours of HBTs obtained from the material growth studies. An on-wafer fast reliability testing equipment will be developed within the project. The reliability improvements will be checked by 3 end-user companies. The HERO'S Consortium is vertically integrated from the source material to final applications. It comprises a well-known commercial supplier of MOCVD wafers, three academic research groups recognised in semiconductor field, 2 R&D centres with strong expertise in semiconductor devices, two end-user companies mostly involved in telecommunication applications and one GaAs foundry fabricating InGaP/GaAs HBTs. Two of these companies are SMEs BE97-5068.