Front
-------------------
P_POL                    Not used
P_N               3      I shouldn't have put it, not used
P_DIF            14      strip implant
P_RES            15      polysilicon
P_CON_P          10      not in use, remove
P_CON_S                  Contact metal - strips
P_MET            12      metal  
P_SPRAY           2      P-stops
scribble         19      Moderation 

Front layers in use: 6 

Layers on the back
------------------
P_DIF_LA          1      implant
P_CON_S_L        29      contacts
P_MET_LA          5      metal
Back layers: 3