LOW-PRESSURE CHEMICAL-VAPOR-DEPOSITION OF POLYCRYSTALLINE SILICON - VALIDATION AND ASSESSMENT OF REACTOR MODELS

The layer thickness of polycrystalline silicon grown in a commercial L PCVD reactor at 25-50 Pa and 850-950 K is accurately simulated with a one-dimensional two-zone model without adjusting any model parameter a nd applying independently determined reaction kinetics. The radial non -uniformity of the layer thickness is limited to 4%. At a surface-to-v olume ratio of 200 m(-1) up to 20% of the growth originates from silyl ene and disilane. This contribution is the cause of the radial non-uni formity.