FRAUNHOFER IISB

Technologies

Fraunhofer IISB

OVERVIEW

Fraunhofer IISB offers early-access to its 2µm SiC CMOS technology including NMOS and PMOS transistors as well as passive components and pn-diodes for integrated circuits. These circuits are capable of operating at temperatures above 300 °C (up to approx. 600 °C). Additional process modules are available for high-voltage devices, isolated transistors and SiC device templates exceeding CMOS circuits.

 

The targeted applications for this technology include integrated circuits beyond silicon for extremely harsh environments including high temperatures and radiation levels with low leakage. Additionally, the technology can be tailored to obtain specialized optical SiC devices and quantum sensor templates.

DETAILS

The double well 2 µm SiC CMOS process consists of 1 Poly and 2 Metal (Pt) layers and includes dedicated ohmic contacts to p+– and n+-doped SiC regions. A thick gate oxide allows peak voltages up to 20 V, and additional dielectric isolation is provided through an active area layer using a field oxide.

 

The standard process flow for this planar technology includes these process modules:

Module
Description
Alignment marks and scribe
Dry etching of the alignment marks for lithography
Implantation
pwell
• Implantation of N and Al
• Masking: Photoresist or oxide (depending on implantation energy)
nwell
pplus
nplus
High temperature annealing
Implant annealing with carbon capping
Active Area
Deposition and structuring of an SiO2 layer by wet etching
Gate
Gate Oxide
Thermal gate oxidation and post-oxidation anneal
PolySi
Deposition and patterning of PolySi layer by dry etching
Ohmic contacts
Field Oxide
Deposition of an SiO2 passivation layer
Spacing
Silicided n & p contacts with dedicated contact metals
p-Ohm
n-Ohm
Metallization
Gate Vias
Via etching through SiO2 passivation layer
Metal 1
Deposition and structuring of the 1st metal layer
Via 2
• Deposition of electrical passivation layer (SiO2 or Si3N4)
• Via etching through passivation layer
Metal 2
Deposition and structuring of the 2nd metal layer
Passivation
Deposition of high temperature pad passivation

The following process module options are available for this technology as front-end-of-line and back-end-of-line process modules on demand for selected wafers:

Optional modules – Please inquire for additional details
RESURF
High-voltage power device implantation layer towards SmartPower ICs
UV
Dedicated implantation for UV diodes towards integrated UV sensing
CUSTOM I2
Custom implantation layer towards specialized custom devices
AL METAL
Low-temp. device metallization (Al) for lower metal resistance
GRIND
Wafer thinning towards advanced packaging / custom devices
SINTER
Backside metallization for silver sintering (high-T packaging)

A basic design kit including design rules, basic electrical device models for NMOS and PMOS transistors, and a process overview are available.

Design rule check, Electrical rule check and Layout-vs-Schematics functionality for Cadence will be provided with a preliminary device library prior to the tape-out date.

 

Delivery

Customers will receive a total of 30 diced samples including electrical test data.
Basic packaging services are available for this early-access technology.

Diced 4H-SiC wafer with integrated circuits and test patterns on tape
© Erik Teuber / Fraunhofer IISB
4H-SiC wafer with sensor arrays and integrated circuits from engineering lot
© Thomas Richter / Fraunhofer IISB