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用大束流密度的钴金属离子注入硅能够直接合成性能良好的薄层硅化物.束流密度为0.25～1.25A/m2,注入量为5×1017cm-2.用透射电子显微镜（TEM）和电子衍射（XRD）分析了注入层结构.结果表明随束流密度的增加,硅化钴相生长,薄层硅化物的方块电阻Rs明显下降.当束流密度为0.75 A/m2时,Rs明显地下降,说明连续的硅化物已经形成.当束流密度为1.25A/m2时,该值达到最小值3.1Ω.XRD分析表明,注入层中形成了3种硅化钴Co2Si,CoSi和CoSi2.经过退火后,Rs进一步地下降,Rs最小可降至2.3Ω,说明硅化钴薄层质量得到了进一步的改善.大束流密度注入和退火后,硅化钴相进一步生长,Co2Si相消失.TEM对注入样品横截面观察表明,连续硅化物层厚度为 90～133 nm.最优的钴注入量和束流密度分别为 5×1017cm-2和 0.50μA/cm2.最佳退火温度和退火时间分别为900℃和10s.高温退火（120℃）仍然具有很低的薄层电阻,这充分说明硅化钴具有很好的热稳定性.用离子注入Co所形成的硅化钴制备了微波功率器件Ohm接触电极,当工作频率为 590～610 MHz,输出功率为 18～20 W时,同常规工艺相比,发射极接触电阻下降到0.13～0.2倍,结果器件的噪声明显地下降,器件质量有了明显的提高.
The high-density thin-layer silicide can be directly synthesized by injecting silicon with a large beam density of cobalt metal ions with a beam density of 0.25-1.25 A / m 2 and an implantation volume of 5 × 10 17 cm -2. Transmission electron microscopy (TEM) The results show that with the increase of the beam current density, the cobalt silicide phase grows and the sheet resistance Rs of the thin layer silicide decreases obviously. When the beam current density is 0.75 A / m2, Rs obviously decreases , Indicating that the continuous silicide has been formed.When the beam density is 1.25A / m2, the value reaches the minimum of 3.1Ω.XRD analysis shows that three kinds of cobalt silicide, Co2Si, CoSi and CoSi2, were formed in the implanted layer. After annealing , Rs decreased further, the minimum Rs could be reduced to 2.3Ω, indicating that the quality of the cobalt suicide thin layer has been further improved. After the large beam current density injection and annealing, the cobalt suicide phase further grows and the Co2Si phase disappears. The results show that the thickness of the continuous silicide layer is 90-133 nm, the optimal amount of cobalt injection and beam current density are 5 × 10 17 cm -2 and 0.50 μA / cm 2, respectively, and the optimum annealing temperature and annealing time are 900 ℃ and 10 s respectively. High temperature annealing (120 ° C) still has a very low TLC , Which fully shows that the cobalt suicide possesses good thermal stability.With the cobalt silicide formed by ion implantation, the Ohm contact electrode of the microwave power device is prepared, and when the operating frequency is 590-610 MHz and the output power is 18-20 W, Compared with the conventional process, the emitter contact resistance decreased to 0.13 ~ 0.2 times, the result of the device noise decreased significantly, the quality of the device has been significantly improved.