Wafer bonding technology and its applications in optoelectronic devices and materials

Direct wafer bonding process has found broad applications in many critical areas including both commercial and state-of-the-art photonic devices and more recently, formation of semiconductor compliant substrates. Using the wafer bonding technology, we have demonstrated 1.3-mu m vertical-cavity surface-emitting lasers (VCSEL's) with a 1-mA continuous-wave (CW) threshold current and 0.83-mA pulsed threshold current. Superior device performance has also been achieved,vith photodetectors and micromachined tunable devices. Applying the wafer bonding process in a novel way, we have fabricated compliant universal substrates on which largely mismatched (e.g., 15% mismatch) heteroepitaxial layers can be grown defect free.