<s>
Solid	B-Algorithm
Logic	I-Algorithm
Technology	I-Algorithm
(	O
SLT	O
)	O
was	O
IBM	O
's	O
method	O
for	O
hybrid	O
packaging	O
of	O
electronic	O
circuitry	O
introduced	O
in	O
1964	O
with	O
the	O
IBM	B-Application
System/360	I-Application
series	O
of	O
computers	O
and	O
related	O
machines	O
.	O
</s>
<s>
IBM	O
chose	O
to	O
design	O
custom	O
hybrid	O
circuits	O
using	O
discrete	O
,	O
flip	O
chip-mounted	O
,	O
glass-encapsulated	O
transistors	B-Application
and	O
diodes	O
,	O
with	O
silk-screened	O
resistors	O
on	O
a	O
ceramic	O
substrate	O
,	O
forming	O
an	O
SLT	O
module	O
.	O
</s>
<s>
SLT	O
was	O
a	O
revolutionary	O
technology	O
for	O
1964	O
,	O
with	O
much	O
higher	O
circuit	O
densities	O
and	O
improved	O
reliability	O
over	O
earlier	O
packaging	O
techniques	O
such	O
as	O
the	O
Standard	B-Device
Modular	I-Device
System	I-Device
.	O
</s>
<s>
It	O
helped	O
propel	O
the	O
IBM	B-Application
System/360	I-Application
mainframe	O
family	O
to	O
overwhelming	O
success	O
during	O
the	O
1960s	O
.	O
</s>
<s>
SLT	O
replaced	O
the	O
earlier	O
Standard	B-Device
Modular	I-Device
System	I-Device
,	O
although	O
some	O
later	O
SMS	O
cards	O
held	O
SLT	O
modules	O
.	O
</s>
<s>
SLT	O
used	O
silicon	O
planar	O
glass-encapsulated	O
transistors	B-Application
and	O
diodes	O
.	O
</s>
<s>
SLT	O
uses	O
dual	O
diode	O
chips	O
and	O
individual	O
transistor	B-Application
chips	O
each	O
approximately	O
square	O
.	O
</s>
<s>
Solid	O
Logic	O
Dense	O
(	O
SLD	O
)	O
increased	O
packaging	O
density	O
and	O
circuit	O
performance	O
by	O
mounting	O
the	O
discrete	O
transistors	B-Application
and	O
diodes	O
on	O
top	O
of	O
the	O
substrate	O
and	O
the	O
resistors	O
on	O
the	O
bottom	O
.	O
</s>
<s>
Each	O
package	O
contains	O
a	O
ceramic	O
wafer	O
with	O
up	O
to	O
four	O
silicon	O
dies	O
on	O
top	O
,	O
each	O
die	O
implementing	O
one	O
transistor	B-Application
or	O
two	O
diodes	O
;	O
and	O
thick-film	O
resistors	O
underneath	O
.	O
</s>
<s>
ULDs	O
were	O
used	O
in	O
the	O
Launch	B-Device
Vehicle	I-Device
Digital	I-Device
Computer	I-Device
and	O
Launch	O
Vehicle	O
Data	O
Adapter	O
of	O
the	O
Saturn	O
V	O
rocket	O
.	O
</s>
<s>
Advanced	O
Solid	B-Algorithm
Logic	I-Algorithm
Technology	I-Algorithm
(	O
ASLT	O
)	O
increased	O
packaging	O
density	O
and	O
circuit	O
performance	O
by	O
stacking	O
two	O
substrates	O
in	O
the	O
same	O
package	O
.	O
</s>
<s>
ASLT	O
is	O
based	O
on	O
the	O
Emitter-follower-coupled-switch	B-General_Concept
used	O
with	O
current-steering	B-General_Concept
logic	I-General_Concept
.	O
</s>
<s>
Monolithic	O
System	O
Technology	O
(	O
MST	O
)	O
increased	O
packaging	O
density	O
and	O
circuit	O
performance	O
by	O
replacing	O
discrete	O
transistors	B-Application
and	O
diodes	O
with	O
one	O
to	O
four	O
monolithic	O
integrated	O
circuits	O
(	O
resistors	O
now	O
external	O
from	O
the	O
package	O
on	O
the	O
module	O
)	O
.	O
</s>
<s>
Circuits	O
used	O
NPN	O
transistors	B-Application
.	O
</s>
