Title :
The influence of titanium capped aluminum on N/sup +//P junction leakage
Author :
Whitwer, Fred ; Haas, Fred ; Lage, Craig
Author_Institution :
Nat. Semicond. Corp., Puyallup, WA, USA
Abstract :
The effects of aluminum capped with titanium on the barrier properties of tungsten/10% titanium (W/10% Ti) are studied. Also, various methods aimed at improving the barrier properties of W/10% Ti are evaluated. It is found that the amount of silicon in the aluminium alloy influences the ability of the W/10% Ti to prevent junction spiking. Use of an aluminum alloy with increased amounts of silicon results in less junction leakage. The cause of this is the intermetallic formed between the aluminum and titanium which has a high solid solubility for silicon. The amount of junction leakage is dramatically improved by stuffing the barrier metal. This is done by annealing the W/10% Ti in a forming gas ambient to form oxy-nitride compounds on the boundaries of the grains.<>
Keywords :
aluminium alloys; copper alloys; leakage currents; metallisation; silicon alloys; titanium; titanium alloys; tungsten alloys; WTi-AlSiCu-Ti; annealing; barrier metal stuffing; barrier properties; intermetallic; junction spiking; n/sup +/-p junction leakage; oxy-nitride compounds; Aluminum alloys; Annealing; Electromigration; Intermetallic; Leakage current; Silicon alloys; Solids; Sputter etching; Titanium; Tungsten;
Conference_Titel :
VLSI Multilevel Interconnection Conference, 1988. Proceedings., Fifth International IEEE
Conference_Location :
Santa Clara, CA, USA
DOI :
10.1109/VMIC.1988.14229
