Conformal and continuous silicon oxide films produced by atomic layer deposition (ALD) are enabling novel processing schemes and integrated device structures. The increasing drive toward lower temperature processing requires new precursors with even higher reactivity. The aminosilane family of precursors has advantages due to their reactive nature and relative ease of use. In this paper, the authors present the experimental results that reveal the uniqueness of the monoaminosilane structure [(R2N)SiH3] in providing ultralow temperature silicon oxide depositions. Disubstituted aminosilanes with primary amines such as in bis(t-butylamino)silane and with secondary amines such as in bis(diethylamino)silane were compared with a representative monoaminosilane: di-sec-butylaminosilane (DSBAS). DSBAS showed the highest growth per cycle in both thermal and plasma enhanced ALD. These findings show the importance of the arrangement of the precursor's organic groups in an ALD silicon oxide process.

This paper reports the influence of BTBAS (bis(tertiarybutylamino)silane), BDEAS (bis(diethylamino)silane), and TDMAS (tris(dimethylamino)silane), three different structures of aminosiliane precursor deposited on silicon oxide by atomic layer deposition. TDMAS showed a 40% lower deposition rate while BTBAS and BDEAS demonstrated superior deposition performance for an ALD process. Amongst BTBAS and BDEAS, BTBAS provided a higher deposition rate and wider temperature window. Bis(amino)silanes provided improved performance relative to tris(amino)silanes.