W Contacted P+N Junction Diode Using Selective W-CVD

• Main Authors: Chen, Shin-Huei, 陳昕輝
• Other Authors: Chen Mao-Chieh
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/30336415065269209489

碩士 === 國立交通大學 === 電子研究所 === 84 === This thesis studies the W contacted p+n junction diode with the W film deposited using the selective W-CVD technique. For the Cu/W/p+n junction diode with a W layer of 300 nm, a thermal treatment at 600 C for 30 min caused slight degradation to the devices characteristics. With formation of a self-aligned WNx layer on the W surface by post CVD-W in situ N2 plasma treatment, the device remained stable after annealing at 600 C for 30 min. However, degradation occurred after 650 C anneal for 30 min, presumably due to the permeation of Cu into TEOS oxide. For the Cu/WNx/W/p+n junction diode with the Cu layer covering the barrier only, the device was able to sustain a 30 min thermal treatment up to 650 C without causing degradation. The WNx layer formed by RTA treatment in NH3 ambient was found to possess a similar barrier capacity against Cu penetration. Although WNx layer formation increased the contact resistance, application of a Ti silicide layer on the Si surface could reduce the resistance effectively. Copper permeates into the TEOS oxide passivation layer easily. The nitrogenized passivation layer could retard the Cu permeation up to 600 C. In a word, the nitridation treatment not only improved the barrier capacity of W layer but also suppressed the permeation of Cu into the passivation layer.