Title :
Improved high frequency performance of AlInAs/GaInAs HBTs through use of low temperature GaInAs
Author :
Stanchina, W. ; Metzger, R. ; Jensen, J. ; Rensch, D. ; Pierce, M. ; Delaney, M. ; Wilson, R. ; Kargodorian, T. ; Allen, Y.
Author_Institution :
Hughes Res. Lab., Malibu, CA, USA
Abstract :
GaInAs grown at lower than normal substrate temperatures was used to reduce the amount of beryllium out-diffusion from the heavily doped bases of AlInAs/GaInAs Npn HBTs. A combined 20-nm-thick spacer structure of p-doped and undoped GaInAs grown at 300 degrees C prevented excessive amounts of beryllium from diffusing into the AlInAs emitter. This allowed base beryllium doping concentrations up to 10/sup 20/ cm/sup -3/ to be achieved, thereby reducing base resistance and increasing f/sub max/ to 70 GHz. A fifteen-stage ring oscillator utilizing these HBTs demonstrated a gate delay of 15.8 ps. The reduced outdiffusion was confirmed by secondary ion mass spectrometry (SIMS) elemental profiles in addition to electrical measurements.<>
Keywords :
III-V semiconductors; aluminium compounds; bipolar integrated circuits; gallium arsenide; heterojunction bipolar transistors; indium compounds; solid-state microwave devices; 15.8 ps; 70 GHz; AlInAs-GaInAs; AlInAs:Be; Be outdiffusion; N-p-n HBT; SIMS elemental profiles; base doping concentrations; base resistance; electrical measurements; fifteen-stage ring oscillator; gate delay; heavily doped bases; high frequency performance; low temperature GaInAs; maximum frequency; spacer structure; substrate temperatures; Doping; Electric resistance; Frequency; Gallium arsenide; Heterojunction bipolar transistors; Laboratories; Light emitting diodes; Photonic band gap; Silicon; Temperature;
Conference_Titel :
Indium Phosphide and Related Materials, 1990. Second International Conference.
Conference_Location :
Denver, CO, USA
DOI :
10.1109/ICIPRM.1990.202978
