First attempt for geometry scaled diode (level=3)

src/spicelib/devices/dio/dio.c

@@ -109,6 +109,15 @@ IFparm DIOmPTable[] = { /* model parameters */
  IOP( "isr",  DIO_MOD_ISR,  IF_REAL, "Recombination saturation current"),
  IOP( "nr",   DIO_MOD_NR,   IF_REAL, "Recombination current emission coefficient"),
 
+ IOP( "lm",  DIO_MOD_LM,  IF_REAL, "Length of metal capacitor (level=3)"),
+ IOP( "lp",  DIO_MOD_LP,  IF_REAL, "Length of polysilicon capacitor (level=3)"),
+ IOP( "wm",  DIO_MOD_WM,  IF_REAL, "Width of metal capacitor (level=3)"),
+ IOP( "wp",  DIO_MOD_WP,  IF_REAL, "Width of polysilicon capacitor (level=3)"),
+ IOP( "xom", DIO_MOD_XOM, IF_REAL, "Thickness of the metal to bulk oxide (level=3)"),
+ IOP( "xoi", DIO_MOD_XOI, IF_REAL, "Thickness of the polysilicon to bulk oxide (level=3)"),
+ IOP( "xm",  DIO_MOD_XM,  IF_REAL, "Masking and etching effects in metal (level=3)"),
+ IOP( "xp",  DIO_MOD_XP,  IF_REAL, "Masking and etching effects in polysilicon (level=3)"),
+
  IP( "d",    DIO_MOD_D,   IF_FLAG, "Diode model")
 };
 

src/spicelib/devices/dio/diodefs.h

@@ -117,6 +117,9 @@ typedef struct sDIOinstance {
     double DIOjunctionSWCap;     /* geometry adjusted junction sidewall capacitance */
     double DIOtRecSatCur; /* temperature adjusted recombination saturation current */
 
+    double DIOcmetal; /* parasitic metal overlap capacitance */
+    double DIOcpoly;  /* parasitic polysilicon overlap capacitance */
+
 /*
  * naming convention:
  * x = vdiode
@@ -235,6 +238,15 @@ typedef struct sDIOmodel {       /* model structure for a diode */
     unsigned DIOrecSatCurGiven : 1;
     unsigned DIOrecEmissionCoeffGiven : 1;
 
+    unsigned DIOlengthMetalGiven : 1;     /* Length of metal capacitor (level=3) */
+    unsigned DIOlengthPolyGiven : 1;      /* Length of polysilicon capacitor (level=3) */
+    unsigned DIOwidthMetalGiven : 1;      /* Width of metal capacitor (level=3) */
+    unsigned DIOwidthPolyGiven : 1;       /* Width of polysilicon capacitor (level=3) */
+    unsigned DIOmetalOxideThickGiven : 1; /* Thickness of the metal to bulk oxide (level=3) */
+    unsigned DIOpolyOxideThickGiven : 1;  /* Thickness of the polysilicon to bulk oxide (level=3) */
+    unsigned DIOmetalMaskOffsetGiven : 1; /* Masking and etching effects in metal (level=3)") */
+    unsigned DIOpolyMaskOffsetGiven : 1;  /* Masking and etching effects in polysilicon (level=3) */
+
     int    DIOlevel;   /* level selector */
     double DIOsatCur;   /* saturation current */
     double DIOsatSWCur;   /* Sidewall saturation current */
@@ -290,6 +302,15 @@ typedef struct sDIOmodel {       /* model structure for a diode */
     double DIOrecSatCur; /* Recombination saturation current */
     double DIOrecEmissionCoeff; /* Recombination emission coefficient */
 
+    double DIOlengthMetal;     /* Length of metal capacitor (level=3) */
+    double DIOlengthPoly;      /* Length of polysilicon capacitor (level=3) */
+    double DIOwidthMetal;      /* Width of metal capacitor (level=3) */
+    double DIOwidthPoly;       /* Width of polysilicon capacitor (level=3) */
+    double DIOmetalOxideThick; /* Thickness of the metal to bulk oxide (level=3) */
+    double DIOpolyOxideThick;  /* Thickness of the polysilicon to bulk oxide (level=3) */
+    double DIOmetalMaskOffset; /* Masking and etching effects in metal (level=3)") */
+    double DIOpolyMaskOffset;  /* Masking and etching effects in polysilicon (level=3) */
+
 } DIOmodel;
 
 /* device parameters */
@@ -372,6 +393,15 @@ enum {
     DIO_MOD_BV_MAX,
     DIO_MOD_ISR,
     DIO_MOD_NR,
+
+    DIO_MOD_LM,
+    DIO_MOD_LP,
+    DIO_MOD_WM,
+    DIO_MOD_WP,
+    DIO_MOD_XOM,
+    DIO_MOD_XOI,
+    DIO_MOD_XM,
+    DIO_MOD_XP,
 };
 
 #include "dioext.h"

src/spicelib/devices/dio/dioload.c

@@ -349,7 +349,8 @@ next1:      if (model->DIOsatSWCurGiven) {              /* sidewall current */
 
                 diffcap = here->DIOtTransitTime*gdb;
                 diffcapSW = here->DIOtTransitTime*gdsw;
-                capd = diffcap + diffcapSW + deplcap + deplcapSW;
+
+                capd = diffcap + diffcapSW + deplcap + deplcapSW + here->DIOcmetal + here->DIOcpoly;
 
                 here->DIOcap = capd;
 

src/spicelib/devices/dio/diomask.c

@@ -178,6 +178,32 @@ DIOmAsk (CKTcircuit *ckt, GENmodel *inModel, int which, IFvalue *value)
         case DIO_MOD_NR:
             value->rValue = model->DIOrecEmissionCoeff;
             return(OK);
+
+        case DIO_MOD_LM:
+            value->rValue = model->DIOlengthMetal;
+            return(OK);
+        case DIO_MOD_LP:
+            value->rValue = model->DIOlengthPoly;
+            return(OK);
+        case DIO_MOD_WM:
+            value->rValue = model->DIOwidthMetal;
+            return(OK);
+        case DIO_MOD_WP:
+            value->rValue = model->DIOwidthPoly;
+            return(OK);
+        case DIO_MOD_XOM:
+            value->rValue = model->DIOmetalOxideThick;
+            return(OK);
+        case DIO_MOD_XOI:
+            value->rValue = model->DIOpolyOxideThick;
+            return(OK);
+        case DIO_MOD_XM:
+            value->rValue = model->DIOmetalMaskOffset;
+            return(OK);
+        case DIO_MOD_XP:
+            value->rValue = model->DIOpolyMaskOffset;
+            return(OK);
+
         default:
             return(E_BADPARM);
         }

src/spicelib/devices/dio/diompar.c

@@ -217,6 +217,40 @@ DIOmParam(int param, IFvalue *value, GENmodel *inModel)
             model->DIOrecEmissionCoeff = value->rValue;
             model->DIOrecEmissionCoeffGiven = TRUE;
             break;
+
+        case DIO_MOD_LM:
+            model->DIOlengthMetal = value->rValue;
+            model->DIOlengthMetalGiven = TRUE;
+            break;
+        case DIO_MOD_LP:
+            model->DIOlengthPoly = value->rValue;
+            model->DIOlengthPolyGiven = TRUE;
+            break;
+        case DIO_MOD_WM:
+            model->DIOwidthMetal = value->rValue;
+            model->DIOwidthMetalGiven = TRUE;
+            break;
+        case DIO_MOD_WP:
+            model->DIOwidthPoly = value->rValue;
+            model->DIOwidthPolyGiven = TRUE;
+            break;
+        case DIO_MOD_XOM:
+            model->DIOmetalOxideThick = value->rValue;
+            model->DIOmetalOxideThickGiven = TRUE;
+            break;
+        case DIO_MOD_XOI:
+            model->DIOpolyOxideThick = value->rValue;
+            model->DIOpolyOxideThickGiven = TRUE;
+            break;
+        case DIO_MOD_XM:
+            model->DIOmetalMaskOffset = value->rValue;
+            model->DIOmetalMaskOffsetGiven = TRUE;
+            break;
+        case DIO_MOD_XP:
+            model->DIOpolyMaskOffset = value->rValue;
+            model->DIOpolyMaskOffsetGiven = TRUE;
+            break;
+
         case DIO_MOD_D:
             /* no action - we already know we are a diode, but this */
             /* makes life easier for spice-2 like parsers */

src/spicelib/devices/dio/diosetup.c

@@ -15,15 +15,21 @@ Modified by Paolo Nenzi 2003 and Dietmar Warning 2012
 #include "diodefs.h"
 #include "ngspice/sperror.h"
 #include "ngspice/suffix.h"
+#include "ngspice/fteext.h"
 
 int
 DIOsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
 {
+    double scale;
+
     DIOmodel *model = (DIOmodel*)inModel;
     DIOinstance *here;
     int error;
     CKTnode *tmp;
 
+    if (!cp_getvar("scale", CP_REAL, &scale, 0))
+        scale = 1;
+
     /*  loop through all the diode models */
     for( ; model != NULL; model = DIOnextModel(model)) {
 
@@ -166,6 +172,31 @@ DIOsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
             model->DIOrecSatCur = 1e-14;
         }
 
+        if(!model->DIOlengthMetal) {
+            model->DIOlengthMetal = 0.0;
+        }
+        if(!model->DIOlengthPoly) {
+            model->DIOlengthPoly = 0.0;
+        }
+        if(!model->DIOwidthMetal) {
+            model->DIOwidthMetal = 0.0;
+        }
+        if(!model->DIOwidthPoly) {
+            model->DIOwidthPoly = 0.0;
+        }
+        if(!model->DIOmetalOxideThick) {
+            model->DIOmetalOxideThick = 10e3;
+        }
+        if(!model->DIOpolyOxideThick) {
+            model->DIOpolyOxideThick = 10e3;
+        }
+        if(!model->DIOmetalMaskOffset) {
+            model->DIOmetalMaskOffset = 0.0;
+        }
+        if(!model->DIOpolyMaskOffset) {
+            model->DIOpolyMaskOffset = 0.0;
+        }
+
         /* loop through all the instances of the model */
         for (here = DIOinstances(model); here != NULL ;
                 here=DIOnextInstance(here)) {
@@ -201,6 +232,13 @@ DIOsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt, int *states)
             here->DIOjunctionCap = model->DIOjunctionCap * here->DIOarea;
             here->DIOjunctionSWCap = model->DIOjunctionSWCap * here->DIOpj;
 
+            here->DIOcmetal = 3.9 * 8.854214871e-12 / model->DIOmetalOxideThick 
+                              * (model->DIOwidthMetal * scale + model->DIOmetalMaskOffset) 
+                              * (model->DIOlengthMetal * scale + model->DIOmetalMaskOffset);
+            here->DIOcpoly = 3.9 * 8.854214871e-12 / model->DIOpolyOxideThick 
+                              * (model->DIOwidthPoly * scale + model->DIOpolyMaskOffset) 
+                              * (model->DIOlengthPoly * scale + model->DIOpolyMaskOffset);
+
             here->DIOstate = *states;
             *states += DIOnumStates;
             if(ckt->CKTsenInfo && (ckt->CKTsenInfo->SENmode & TRANSEN) ){