4.3.2 The PROMIS-NT Unit System

While the mere structure of (4.1) - (4.10) requires only the usage of matching unit dimensions for the various coefficients and quantities, the VISTA process integration demand for some more rigorous assumptions. The PIF interface of PROMIS-NT ensures that the units depicted in Table 4.3 are used for all predefined physical attributes.

User defined quantities require no explicit assignment of a certain unit. Their values are stored without any unit information and are passed to subsequent simulators like numerical attributes. Therefore the user has to ensure that the definition of the coefficients of (4.1) - (4.10) assumes the right unit strings.

Table 4.3: PROMIS-NT units

Attribute	Unit	Comment
time	$s$	simulation time
temperatures	$K$	process temperature
lengths	${\mu}m$	for explicit values of lateral and vertical coordinates
concentrations	$cm^{-3}$	for default quantities which represent concentrations
stress tensor elements	$dyne/cm^2$	Sxx, Sxy, Syy
velocity	$cm/s$	vx,vy
grain size	$cm$	poly silicon grain size
grain orientation	$1$	poly silicon grain orientation