Showing papers by "Bobby Brar published in 1997"
12 Oct 1997
TL;DR: The first monolithic flash RTD/HFET analog-to-digital converter (ADC) is demonstrated, demonstrating the combination of resonant tunneling diodes and heterostructure field-effect transistors for implementing microwave digital and mixed-signal applications.
Abstract: The combination of resonant tunneling diodes (RTDs) and heterostructure field-effect transistors (HFETs) provides a versatile technology for implementing microwave digital and mixed-signal applications. Here we demonstrate the first monolithic flash RTD/HFET analog-to-digital converter (ADC). The first pass ADC achieved 2.7 effective bits at 2 GSps. The one bit quantizer achieved a single tone spurious free dynamic range (SFDR) of greater than 40 dB at 2 GSps for a 220 MHz single tone input with dithering.
62 citations
12 Oct 1997
TL;DR: In this paper, a three-dimensional large-scale integration (LSI) process for fabrication of resonant tunneling diodes and heterojunction field effect transistors on InP has been demonstrated.
Abstract: A three-dimensional large-scale integration (LSI) process for fabrication of resonant tunneling diodes and heterojunction field-effect transistors on InP has been demonstrated, combining two of today's fastest semiconductor devices. Demonstrations of this technology now include multigigahertz digital and mixed-signal circuits and ultralow power SRAM circuits; 25 to 100 GHz circuits are clearly in range for this technology.
26 citations
TL;DR: In this paper, the fundamental device requirements for silicon optical and tunneling devices are outlined and progress on silicon heterojunction development towards demonstration of silicon-based RTDs is described.
Abstract: The roadmap for silicon device technology has been drawn, extending to the year 2010, and featuring a CMOS transistor with a gate length of 0.07 μm [{xc1}]. Beyond this point, silicon heterojunctions could provide a means to further device scaling. Silicon heterojunctions could also bring new devices to the silicon substrate including light emitters and detectors, and resonant tunneling diodes (RTDs). Today SiGe/Si and SiGeC/Si heterojunctions are receiving the greatest attention, but heterojunctions now being developed to realize silicon RTDs are increasing the heterojunction options for silicon-based quantum-well and optical devices. Here we outline the fundamental device requirements for silicon optical and tunneling devices and describe progress on silicon heterojunction development towards demonstration of silicon-based RTDs. Materials now under study include, ZnS, crystalline oxides and nitrides; new processes could provide methods for forming crystalline materials over amorphous barriers.
6 citations