Chemical vapor deposition of titanium nitride thin films from tetrakis(dimethylamido)titanium and hydrazine as a coreactant

Abstract

Hydrazine was used as a coreactant with tetrakis(dimethylamido)titanium for the low-temperature chemical vapor deposition of TiN between 50 and 200°C. The TiN film-growth rates ranged from 5 to 45 nm/min. Ti:N ratios of approximately 1:1 were achieved. The films contain between 2 and 25 at.% carbon, as well as up to 36 at.% oxygen resulting from diffusion after air exposure. The resistivity of these films is approximately 10 4 ⍀ cm. Annealing the films in ammonia enhances their crystallinity. The best TiN films were produced at 200°C from a 2.7% hydrazine-ammonia mixture. The Ti:N ratio of these films is approximately 1:1, and they contain no carbon or oxygen. These films exhibit the highest growth rates observed.

Early Transition Metal Complexes Containing 1,2,4-Triazolato and Tetrazolato Ligands: Synthesis, Structure, and Molecular Orbital Studies

“…While ammonia is by far the most widely used nitrogen source compound in film growth, the high stability of ammonia and concomitant high film deposition temperatures has led to increasing consideration of alternative nitrogen source compounds in the past several years within the context of GaN and TiN film growth. 86,[97][98][99][100][101][102][103][104][105][106][107] Hydrazine and alkylhydrazines have been the focus of most of the effort; however, nitrogen heterocycles such as those described herein are potentially useful source compounds. 86,104 Experimental Section General Considerations.…”

“…The long-term goal of our research is to explore new nitrogen source compounds that can be used to grow metal nitride phases by chemical vapor deposition techniques. While ammonia is by far the most widely used nitrogen source compound in film growth, the high stability of ammonia and concomitant high film deposition temperatures has led to increasing consideration of alternative nitrogen source compounds in the past several years within the context of GaN and TiN film growth. ,− Hydrazine and alkylhydrazines have been the focus of most of the effort; however, nitrogen heterocycles such as those described herein are potentially useful source compounds. , …”

Chemistry of Diffusion Barrier Film Formation: Adsorption and Dissociation of Tetrakis(dimethylamino)titanium on Si(100)-2 × 1

“…The first approach to deposit clean TiN films involves the simultaneous exposure of TDMAT and ammonia to the surface. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] The reaction between these two molecules (known as transamination) can effectively lower the presence of carbon by insertion of NH 2 and elimination of dimethylamine:…”

“…In particular, since titanium nitride (TiN) can act as a diffusion barrier between the semiconductor base (typically silicon) and a metallic interconnect, , this material is of capital importance in semiconductor processing. For this reason, the deposition of TiN has been investigated extensively. ,,− …”

“…A number of important efforts has been directed toward the minimization of the carbon content in such films, usually involving a thermal or plasma-stimulated posttreatment. ,,− A second dosing agent, such as ammonia, has also been used to decrease carbon content in the films in two different ways. The first approach to deposit clean TiN films involves the simultaneous exposure of TDMAT and ammonia to the surface. − The reaction between these two molecules (known as transamination) can effectively lower the presence of carbon by insertion of NH 2 and elimination of dimethylamine: The second, and the most promising, approach is atomic layer deposition, ALD, where TDMAT and NH 3 are dosed in an alternate fashion. ,− This layer-by-layer deposition offers the possibility of building films with a thickness of several nanometers but requires a complete understanding of the surface reactions that take place during the process …”