Investigation of etching properties of metal nitride/high-k gate stacks using inductively coupled plasma Export

@inproceedings{25, abstract = {Etching properties of metal nitrides (TaN, TiN, and HfN)/high dielectric constant material (HfO2) gate stacks in Cl2 and HBr were investigated using inductively coupled plasma. The linear dependence of etch rates on the square root of bias voltage indicates the dominance of ion-induced etch mechanism of the metal nitrides. This phenomenon is well explained by internal binding energy of substrate, evaporation temperature, and Gibb's free energy (Gf[degree]" align="middle">) of formation of byproducts. The addition of O2 in Cl2 and HBr decreased etch rates of the metal nitrides and HfO2; however, for O2 concentration lower than 1.5\% in Cl2, a slight increase in etch rates of the metal nitrides was observed. X-ray photoelectron spectroscopy revealed that residues remain more on the sidewalls of gate stacks than the bottom of spaces between gates. The addition of O2 and the use of a SiO2 mask to increase etch selectivity of metal nitrides with respect to high-k dielectric increased surface roughness and formed micromasks on the etched surface. The optical emission signals from N, Cl, and Ta–Cl byproducts were sensitive enough to control the etch endpoints of the TaN/HfO2 stack structures. {\copyright}2005 American Vacuum Society}, author = {Hwang, Wan S. and Chen, Jinghao and Yoo, Won J. and Bliznetsov, Vladimir}, citeulike-article-id = {507874}, citeulike-linkout-0 = {http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JVTAD6000023000004000964000001&idtype=cvips&gifs=yes}, citeulike-linkout-1 = {http://link.aip.org/link/?JVA/23/964}, citeulike-linkout-2 = {http://dx.doi.org/10.1116/1.1927536}, comment = {Empilage : * masque dur (SiO2 70nm) / TaN ou TiN ou HfN (100nm) / HfO2 (par ALD 6nm) / Si * Photoresist masque / BARC / TaN ou TN ou HfN (150nm) / HfO2 (par ALD 6 nm) / Si Tous les m\'{e}taux sont d\'{e}pos\'{e}s par PVD Commentaires : Conditions de l'ICP : Cl2/HBr/O2 Ps = 400W, Vbias = -200V, 10 mTorr. Les essais montrent que l'ER des m\'{e}taux d\'{e}pend du bombardement ionique : variation lin\'{e}aire de ER avec la racine carr\'{e}e de Vbias. L'ajout d'O2 augmente la rugosit\'{e} en surface du m\'{e}tal que ce soit avec Cl2 ou HBr. ER (m\'{e}taux) avec Cl2 > qu'avec HBr. }, doi = {10.1116/1.1927536}, keywords = {etching, hbr-cl2-o2, hfn, icp, nitrogen, optical-emission-spectroscopy, tan, tin, volatility}, number = {4}, pages = {964--970}, posted-at = {2006-02-17 15:42:40}, priority = {0}, publisher = {AVS}, title = {Investigation of etching properties of metal nitride/high-k gate stacks using inductively coupled plasma}, url = {http://dx.doi.org/10.1116/1.1927536}, volume = {23}, year = {2005} }

TY - CONF ID - 25 L3 - citeulike-article-id:507874 N2 - Etching properties of metal nitrides (TaN, TiN, and HfN)/high dielectric constant material (HfO2) gate stacks in Cl2 and HBr were investigated using inductively coupled plasma. The linear dependence of etch rates on the square root of bias voltage indicates the dominance of ion-induced etch mechanism of the metal nitrides. This phenomenon is well explained by internal binding energy of substrate, evaporation temperature, and Gibb's free energy (Gf[degree]" align="middle">) of formation of byproducts. The addition of O2 in Cl2 and HBr decreased etch rates of the metal nitrides and HfO2; however, for O2 concentration lower than 1.5% in Cl2, a slight increase in etch rates of the metal nitrides was observed. X-ray photoelectron spectroscopy revealed that residues remain more on the sidewalls of gate stacks than the bottom of spaces between gates. The addition of O2 and the use of a SiO2 mask to increase etch selectivity of metal nitrides with respect to high-k dielectric increased surface roughness and formed micromasks on the etched surface. The optical emission signals from N, Cl, and Ta–Cl byproducts were sensitive enough to control the etch endpoints of the TaN/HfO2 stack structures. ©2005 American Vacuum Society IS - 4 EP - 970 TI - Investigation of etching properties of metal nitride/high-k gate stacks using inductively coupled plasma PB - AVS VL - 23 SP - 964 KW - etching KW - hbr-cl2-o2 KW - hfn KW - icp KW - nitrogen KW - optical-emission-spectroscopy KW - tan KW - tin KW - volatility N1 - Empilage : * masque dur (SiO2 70nm) / TaN ou TiN ou HfN (100nm) / HfO2 (par ALD 6nm) / Si * Photoresist masque / BARC / TaN ou TN ou HfN (150nm) / HfO2 (par ALD 6 nm) / Si Tous les métaux sont déposés par PVD Commentaires : Conditions de l’ICP : Cl2/HBr/O2 Ps = 400W, Vbias = -200V, 10 mTorr. Les essais montrent que l’ER des métaux dépend du bombardement ionique : variation linéaire de ER avec la racine carrée de Vbias. L’ajout d’O2 augmente la rugosité en surface du métal que ce soit avec Cl2 ou HBr. ER (métaux) avec Cl2 > qu’avec HBr. AU - Hwang, Wan AU - Chen, Jinghao AU - Yoo, Won AU - Bliznetsov, Vladimir PY - 2005/// UR - http://dx.doi.org/10.1116/1.1927536 ER -