Tunnel diodes need degenerately doped junction to optimum performance. They are fabricated using the Molecular Beam Epitaxial method. This method yields good degenerately doped junctions. However it is not clear whether the process can be used with 300 mm wafer technology due to the demand for a high thermal budget. Proximity Rapid Thermal Diffusion (PRTD) uses the RTP tool for its thermal processing. The amount of time used for the processing is in seconds which yields to a low thermal budget. Moreover RTP tools are a common place in the industry and hence comparatively, PRTD is easy to integrate into the wafer fabrication process. Tunneling diodes are fabricated using the proximity diffusion technique where a dopant is diffused from a source wafer to a device wafer in a RTP chamber. The resulting devices yielded PVCR of 2.1 and a current density of 160 mA/cm2 at 300K. The performance of this device is better than the device which was fabricated before at 850 °C. This paper discusses the process flow and the results of the fabricated devices.
"Fabrication of an Esaki Tunneling Diode by Proximity Rapid Thermal Diffusion,"
Journal of the Microelectronic Engineering Conference: Vol. 17
, Article 6.
Available at: http://scholarworks.rit.edu/ritamec/vol17/iss1/6