Selective reactive ion etching of tungsten films in CHF[sub 3] and other fluorinated gases Export

@article{27, abstract = {The use of reactive ion etching (RIE ) with fluorinated gas plasmas, such as SF6, CF4, CBrF3, and CHF3 mixed with oxygen, to achieve selective patterning of tungsten films is reported. The etch rates of W, Si, and SiO2 were measured as a function of oxygen percentage in fluorinated gas plasmas under various conditions. Experiments on selectivity indicate that a CHF3/70\%O2 mixture under 20 sccm, 200 W, 20 mTorr etching conditions results in W:Si and W:SiO2 etch rate ratios of 1.6:1 and 1.8:1, respectively. Optimized W:Si and W:SiO2 selectivity ratios 4:1 and 4.8:1 have been obtained at 60 mTorr/150 W and 260 mTorr/200 W plasma conditions. For reverse selectivity, the optimum W:SiO2 etch rate ratio measured is 1:4.6 in pure CHF3 gas. The optimum W:Si reverse selectivity of 1:11.6 is obtained with an SF6/5\%O2 mixture plasma. A vertical-to-lateral etch ratio of 4:1 was measured with CHF3/70\%O2, 200 W, 10 mTorr, 20 sccm. The etching mechanisms of tungsten due to chemical and physical processes in various fluorocarbon gases under the RIE mode have been investigated and the role of etching species such as fluorine, bromine, and oxygen is discussed.}, author = {Pan, W. S. and Steckl, A. J.}, citeulike-article-id = {524191}, citeulike-linkout-0 = {http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JVTBD9000006000004001073000001&idtype=cvips&gifs=yes}, citeulike-linkout-1 = {http://link.aip.org/link/?JVB/6/1073}, citeulike-linkout-2 = {http://dx.doi.org/10.1116/1.584300}, comment = {Empilage : Masque Al / W (300 \`{a} 500nm) / Si Commentaires: Les conditions initiales de gravure sont : 200W, 20sccm (d\'{e}bit total), 20mTorr · Influence de la pression : A 20mTorr, le rapport vitesse verticale/vitesse horizontale est de 2.3/1 ce qui est mauvais. Si on opte pour 60mTorr, la gravure n'est plus du tout anisotrope, en revanche pour 10mTorr, on obtient un rapport de 4.1/1. L'ER de Si et W d\'{e}pend fortement de la quantit\'{e} d'O2 pr\'{e}sent dans le plasma et de la concentration de fluor. }, doi = {10.1116/1.584300}, journal = {Journal of Vacuum Science \& Technology B: Microelectronics and Nanometer Structures}, keywords = {cbrf3, cf4, chf3, plasma, rie, sf6, tungsten}, number = {4}, pages = {1073--1080}, posted-at = {2006-02-28 14:43:21}, priority = {0}, publisher = {AVS}, title = {Selective reactive ion etching of tungsten films in CHF[sub 3] and other fluorinated gases}, url = {http://dx.doi.org/10.1116/1.584300}, volume = {6}, year = {1988} }

TY - JOUR ID - 27 L3 - citeulike-article-id:524191 N2 - The use of reactive ion etching (RIE ) with fluorinated gas plasmas, such as SF6, CF4, CBrF3, and CHF3 mixed with oxygen, to achieve selective patterning of tungsten films is reported. The etch rates of W, Si, and SiO2 were measured as a function of oxygen percentage in fluorinated gas plasmas under various conditions. Experiments on selectivity indicate that a CHF3/70%O2 mixture under 20 sccm, 200 W, 20 mTorr etching conditions results in W:Si and W:SiO2 etch rate ratios of 1.6:1 and 1.8:1, respectively. Optimized W:Si and W:SiO2 selectivity ratios 4:1 and 4.8:1 have been obtained at 60 mTorr/150 W and 260 mTorr/200 W plasma conditions. For reverse selectivity, the optimum W:SiO2 etch rate ratio measured is 1:4.6 in pure CHF3 gas. The optimum W:Si reverse selectivity of 1:11.6 is obtained with an SF6/5%O2 mixture plasma. A vertical-to-lateral etch ratio of 4:1 was measured with CHF3/70%O2, 200 W, 10 mTorr, 20 sccm. The etching mechanisms of tungsten due to chemical and physical processes in various fluorocarbon gases under the RIE mode have been investigated and the role of etching species such as fluorine, bromine, and oxygen is discussed. IS - 4 JF - Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures EP - 1080 TI - Selective reactive ion etching of tungsten films in CHF[sub 3] and other fluorinated gases PB - AVS VL - 6 SP - 1073 KW - cbrf3 KW - cf4 KW - chf3 KW - plasma KW - rie KW - sf6 KW - tungsten N1 - Empilage : Masque Al / W (300 à 500nm) / Si Commentaires: Les conditions initiales de gravure sont : 200W, 20sccm (débit total), 20mTorr · Influence de la pression : A 20mTorr, le rapport vitesse verticale/vitesse horizontale est de 2.3/1 ce qui est mauvais. Si on opte pour 60mTorr, la gravure n’est plus du tout anisotrope, en revanche pour 10mTorr, on obtient un rapport de 4.1/1. L’ER de Si et W dépend fortement de la quantité d’O2 présent dans le plasma et de la concentration de fluor. AU - Pan, WS AU - Steckl, AJ PY - 1988/// UR - http://dx.doi.org/10.1116/1.584300 ER -