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la situ resistance versus temperature or time for reactions between 32 and 57.5 nm of titanium and undoped or doped polycrystalline silicon (boron, arsenic, or phosphorus, 7.9X1019-3.0X1020/cm3) has been measured and no clear correlation was found between the activation energy for the formation of the industrially important low-resistance C54-TiSia phase and its formation temperature. It is also demonstrated that with certain moderate doping levels typical of complementary metal-oxide-semiconductor manufacturing, boron or phosphorus-doped polycrystalline silicon can delay the formation of C5CTiSia more than arsenic-doped polycrystalline silicon. Finally, by using in situ resistance measurements, it is demonstrated that the "two-step" thermal annealing process similar to a salicide process requires less thermal annealing time at high temperatures to form C54-TiSi, than a single temperature.

We report a stack structure which utilizes an in-plane exchange-biased magnetic layer to influence the coercivity of the bottom CoFeB layer in a CoFeB/MgO/CoFeB perpendicular magnetic tunnel junction. By employing a thickness wedge deposition technique, we were able to study various aspects of this stack using vibrating sample magnetometer including: (1) the coupling between two CoFeB layers as a function of MgO thickness; and (2) the coupling between the bottom CoFeB and the in-plane magnetic layer as a function of Ta spacer thickness. Furthermore, modification of the bottom CoFeB coercivity allows one to measure tunneling magnetoresistance and resistance-area product (RA) of CoFeB/MgO/CoFeB in this pseudo-spin-valve format using current-in-plane-tunneling technique, without resorting to (Co/Pt)n or (Co/Pd)n multilayer pinning.

A full Co20Fe60B20\MgO\ Co20Fe60B20 perpendicular magnetic tunnel junction (pMTJ) with (Co\Pt) multilayers as pinning layers and different functional multilayers stacks were made and annealed at different temperatures. The tunneling magnetoresistance ratio (TMR) and MgO barrier resistance-area product (RA) were measured and analyzed as a function of annealing temperature. The TMR of pMTJs dramatically declines with increasing annealing temperatures from 320 °C to 400 °C while the RA increases with temperature from 375 °C to 450 °C. The pMTJs and partial stacks were also measured in a vibrating sample magnetometer (VSM). We found that the (Co\Pt) multilayers are very stable and maintain a magnetization direction perpendicular to the film plane up to 450 °C. However, the magnetization direction of the CoFeB above and below the MgO barrier rotates from perpendicular to in-plane with increasing annealing temperature. Furthermore, the CoFeB layer influences the adjacent (Co\Pt) layers to rotate at the same time. The pMTJs’ elemental depth profiles in the as deposited and annealed states were determined by Secondary Ion Mass Spectrometry (SIMS). We found that Boron and Tantalum migrate towards the top of the stack. The other elements (Platinum, Cobalt, Ruthenium, and Magnesium) are very stable and do not interdiffuse during annealing up to 450°C.

In various device fabrication processes, such as in metal gate and low resistance word line fabrication, one needs to be able to oxidize Si without oxidizing metals present. We developed such a process using a combination of H2 and O2 in the H2 rich regime. The process developed is safe and is production worthy with excellent uniformity.When carrying out the selective oxidation using H2/O2, a high Si oxidation rate is preferred which requires a high oxygen concentration. At the same time, the increase in metal sheet resistance, if any, must be small. We found that with an oxygen concentration as high as 20%, the increase in W sheet resistance is small. We present data on the oxidation rate of Si under different conditions as well as the selectivity of the process with respect to W and WN.