Adhesion of Chemical Vapor Deposited Boron Carbo-nitride to Dielectric and Copper Films

Abstract

The interfacial adhesion energy was studied using the four-point bend method for boron carbo-nitride (BC x N y ) deposited on dielectric and copper films. Twenty-five nanometer BC x N y films were deposited by chemical vapor deposition at 360°C and 1 Torr using dimethylamine borane with no coreactant, NH 3 , or C 2 H 4 , producing different composition films, BC 0.37 N 0.15 , BC 0.11 N 0.49 , BC 0.92 N 0.07 , with dielectric constants of 4.1, 4.2, and 3.8, respectively. BC x N y films were deposited on dense and porous dielectrics, and copper. BC x N y films adhered strongly to the dielectric films and the composite beams snapped before debonding, revealing that the critical debond energy G c exceeded 10 J/m 2 . The adhesion of BC x N y to oxidized copper increased with carbon content in the film, with the BC 0.92 N 0.07 film beams snapping, and is possibly related to covalent bonding between surface oxygen and carbon in the film. a) Present address: Texas Instruments, 13560 North Central Expressway, Dallas, TX 75243.

Dielectric Barrier, Etch Stop, and Metal Capping Materials for State of the Art and beyond Metal Interconnects

“…434,439 Related CVD a-BCN:H films have been reported to have slightly lower k values of 3.7-4.6 with similar mass densities. 444,445 These films have exhibited good adhesion strengths to Cu and low-k a-SiOC:H ILDs 445 and similar TDDB lifetimes to a-SiCN:H in Cu gated metal-insulator-semiconductor (MIS) capacitor devices. 446 From a DB perspective, CVD a-BCN:H films as thin as 4 nm have been demonstrated as porous ILD pore sealants, 447 and as a Ge passivation and surface oxidation diffusion barrier.…”

Elaboration and quantitative investigation of BCN‐type films by dynamic SIMS using the MCsx+ mode

“…[1,2] For such an application, the thickness of the BCN barrier films is about 5 to 10 nm. Adequate reliability characterization of their anticopper-diffusion capacity requires the use of dynamic SIMS, which combines high depth resolution and high sensitivity to quantify matrix and the diffused impurity species in BCN films.…”