def genLayout( self):
"""Create the layout. Main body of geometric construction code.
"""
Term( "D", TermType.INPUT_OUTPUT)
Term( "G", TermType.INPUT)
Term( "S", TermType.INPUT_OUTPUT)
Term( "B", TermType.INPUT_OUTPUT)
# Create poly
bbox = Box( -self.endcap, 0, (self.width + self.endcap), self.length)
polyRect = Rect( self.gateLayer, bbox)
Pin( "G", "G", Rect( self.gateLayer, bbox))
# Create source contact
contact = self.createContact( "S", Direction.SOUTH, polyRect, self.sourceDiffOverlap)
bottom = contact.getBBox().top
# Create drain contact
contact = self.createContact( "D", Direction.NORTH, polyRect, self.drainDiffOverlap )
top = contact.getBBox().bottom
# Create diffusion
Rect( self.diffLayer, Box( 0, bottom, self.width, top))
Rect( self.implantLayer, Box( 0, bottom, self.width, top)) #create nonenclosing implant layer
# Create other outline layers
all = Grouping( "all", self.getComps())
self.fgAddEnclosingRects( all, self.encLayers)
def createGateCont(self,
gateRect=False,
coverage=1.0,
stretch=False,
terminal=False):
"""Create a gate contact by instantiating a poly contact PyCell.
Arguments:
gateRect - (PhysicalComponent) Gate rectangle for alignment.
coverage - (float ) Percentage of poly width to be covered
by contact
stretch - (string ) Name of stretch handle property for
gate contact
"""
gateCont = ViaInstance(
"pcont",
ParamArray(),
None,
"I%d" % self.instance,
)
self.place(gateCont, Direction.SOUTH, gateRect, 0)
width = self.l * coverage
gateCont.resize(
width=width,
via=self.contact,
metalLayer=self.poly,
)
# Create overlapping poly rectangle for stretch handle
polyRect = gateCont.promoteMetal(self.poly)
bbox = polyRect.getBBox()
width = max(width, bbox.getWidth()) / 2
center = bbox.getCenterX()
bbox.setLeft(center - width)
bbox.setRight(center + width)
polyRect.setBBox(bbox)
# Stretch handle for gate contact coverage
stretchHandle(
shape=polyRect,
name=("stretch%d" % self.instance),
parameter=stretch,
location=Location.CENTER_RIGHT,
direction=Direction.EAST_WEST,
stretchType="relative",
userScale="1.0",
userSnap="0.0025",
minVal=0.0,
maxVal=1.0,
)
# Create weakly-connected pins
if terminal:
Pin(("%sC%d" % (terminal, self.instance)), terminal,
Rect(self.poly, bbox))
self.instance += 1
return (gateCont)
def createContact( self, terminal, location, polyRect, moreOverlap):
"""Create the contact for source or drain.
Arguments:
terminal - (string) Name of terminal for pin.
location - (NORTH||SOUTH) Relative location to place contact.
polyRect - (PhysicalComponent::Rect) Shape to align contact.
moreOverlap - (float) Amount of additional diffusion overlap.
"""
contact = Contact( self.diffLayer, self.xtorFillLayer, terminal, routeDir1 = Direction.EAST_WEST, routeDir2 = Direction.EAST_WEST)
# Placement uses poly-to-diffusion spacing for dogbone
# Demonstrate how dogbone should be done.
isDogBone = contact.getBBox( self.diffLayer).getWidth() > self.width
if isDogBone:
self.fgPlace( contact, location, polyRect)
else:
self.fgPlace( contact, location, polyRect, ShapeFilter([self.diffLayer], False))
cbox = contact.getBBox( self.diffLayer)
contact.moveBy( (cbox.left % self.grid), 0)
if not isDogBone:
pbox = polyRect.getBBox()
contact.stretchTowards( Direction.EAST, pbox.right - self.endcap)
contact.stretchTowards( Direction.WEST, pbox.left + self.endcap)
Pin( terminal, terminal, Rect( self.xtorFillLayer, contact.getBBox( self.xtorFillLayer)))
# Add additional diffusion overlap
cbox = contact.getBBox( self.diffLayer)
if moreOverlap:
if location == Direction.NORTH:
cbox.setTop( cbox.top + moreOverlap)
elif location == Direction.SOUTH:
cbox.setBottom( cbox.bottom - moreOverlap)
else:
raise ValueError, "Unsupported Direction for more diffusion overlap."
Rect( self.diffLayer, cbox)
return( contact)
def createSourceDrain( self,
diffusionType="full",
withContact=True,
x=0,
y=0,
coverage=1.0,
stretch=False,
terminal=False):
"""Create a source or drain diffusion.
Option to create diffusion contact instance.
Option to create matching diffusion terminal.
Option to create a stretch handle property.
Override this method to create custom contacts.
Arguments:
diffusionType - (string) "full", "left", "right"
withContact - (boolean) Create contact
x - (float ) x coordinate for center of contact
y - (float ) y coordinate for lower diffusion edge
coverage - (float ) Percentage of source/drain diffusion to
be covered by contact
stretch - (string ) Name of stretch handle property
"""
# Create source/drain contact
if withContact:
diffCont = ViaInstance(
"dcont",
ParamArray( origin="lowerCenter"),
None,
"I%d" % self.instance,
)
diffCont.setOrigin( Point(x, y-0.02))
height = self.w * coverage
diffCont.resize(
height = height,
via = self.contact,
metalLayer = self.diffusion,
)
# Create overlapping diffusion rectangle for stretch handle
diffRect = diffCont.promoteMetal( self.diffusion)
bbox = diffRect.getBBox()
height = max( height, bbox.getHeight())
bbox.setTop( bbox.getBottom() + height)
diffRect.setBBox( bbox)
# Stretch handle for diffusion contact coverage
stretchHandle(
shape = diffRect,
name = ("stretch%d" % self.instance),
parameter = stretch,
location = Location.UPPER_CENTER,
direction = Direction.NORTH_SOUTH,
stretchType = "relative",
userScale = "1.0",
userSnap = "0.0025",
minVal = 0.0,
maxVal = 1.0,
)
self.instance += 1
# Create source/drain diffusion
if withContact:
bbox = Box(
bbox.getLeft(), y,
bbox.getRight(), (y + self.w),
)
else:
if (diffusionType == "left"):
bbox = Box(
x, y,
(x + self.GateSpaceDiv2), (y + self.w),
)
elif (diffusionType == "right"):
bbox = Box(
(x - self.GateSpaceDiv2), y,
x, (y + self.w),
)
elif (diffusionType == "full"):
bbox = Box(
(x - self.GateSpaceDiv2), y,
(x + self.GateSpaceDiv2), (y + self.w),
)
else:
raise ValueError, "Unknown: diffusionType=%s" % diffusionType
if terminal:
p0 = Pin(
terminal,
terminal,
Rect( self.diffusion, bbox)
)
pinRect = p0.getShapes()[0]
autoAbutment(
pinRect,
self.w,
[ Direction.WEST],
"cniMOS",
abut2PinEqual = [ { "spacing":0.0}, { "diffLeftStyle":"DiffHalf" }, { "diffLeftStyle":"DiffHalf" } ],
abut2PinBigger = [ { "spacing":0.0}, { "diffLeftStyle":"DiffEdgeAbut" }, { "diffLeftStyle":"DiffEdgeAbut" } ],
abut3PinBigger = [ { "spacing":0.0}, { "diffLeftStyle":"ContactEdgeAbut2"}, { "diffLeftStyle":"ContactEdgeAbut2"} ],
abut3PinEqual = [ { "spacing":0.0}, { "diffLeftStyle":"DiffAbut" }, { "diffLeftStyle":"ContactEdgeAbut2"} ],
abut2PinSmaller = [ { "spacing":0.0}, { "diffLeftStyle":"DiffEdgeAbut" }, { "diffLeftStyle":"DiffEdgeAbut" } ],
abut3PinSmaller = [ { "spacing":0.0}, { "diffLeftStyle":"DiffEdgeAbut" }, { "diffLeftStyle":"DiffEdgeAbut" } ],
noAbut = [ { "spacing":0.4}],
function = "cniAbut",
#shape = pinRect,
#abutDirection = diffusionType,
#abutClass = "cniMOS",
#abutFunction = "cniAbut",
#spacingRule = self.DiffSpace,
)
else:
pinRect = Rect( self.diffusion, bbox)
return( pinRect)
def createGate( self,
x=0,
y=0,
terminal=False):
"""Create the poly rectangle which represents the MOS
transistor gate.
Override this method to create custom gates.
Arguments:
x - (integer) x coordinate of gate center
y - (integer) y coordinate of lower diffusion edge
"""
left = x - self.lDiv2
right = x + self.lDiv2
# Create transistor gate
gateRect = Rect( self.poly,
Box( left, (y - self.Endcap),
right, (y + self.w + self.Endcap),
)
)
# Stretch handles for w & l
stretchHandle(
shape = gateRect,
name = ("stretch%d" % self.instance),
parameter = "w",
location = Location.UPPER_CENTER,
direction = Direction.NORTH_SOUTH,
display = ("w = %.2f" % self.w),
stretchType = "relative",
userScale = "1.0",
userSnap = "0.0025",
)
stretchHandle(
shape = gateRect,
name = ("stretch%d" % self.instance),
parameter = "l",
location = Location.CENTER_RIGHT,
direction = Direction.EAST_WEST,
display = ("l = %.2f" % self.l),
stretchType = "relative",
userScale = "1.0",
userSnap = "0.0025",
)
# Create weakly-connected pins
if terminal:
# Bottom gate pin
Pin(
"%sS%d" % (terminal, self.instance),
terminal,
Rect(
self.poly,
Box( left, (y - self.Endcap),
right, y,
)
)
)
# Top gate pin
Pin(
"%sN%d" % (terminal, self.instance),
terminal,
Rect(
self.poly,
Box( left, (y + self.w),
right, (y + self.w + self.Endcap),
)
)
)
self.instance += 1
return( gateRect)