One of the main reasons for the shortage of chips since the beginning of 2021 is the growing demand for automobiles and consumer goods whose main parts are driven by electronics. But researchers from the Indian Institute of Science (IISc) have collaborated with a semiconductor foundry under the Indian government’s IMPRINT program, which may provide a solution to this problem.
The IISc team began developing an indigenous technology platform to fabricate automotive (analog) chips to be used for commercial and mission-critical applications. IMPRINT is the first joint Pan-IIT + IISc initiative supported by the Ministry of Education to address key scientific and technical challenges facing India and champion to enable, empower and embolden the nation for inclusive growth and autonomy.
An IISc statement read: “Automotive chips are different from conventional processor chips used in devices such as smartphones and laptops. An automotive chip (also known as a power ASIC) must handle various tasks simultaneously, including instrumentation, sensing, and control of various electromechanical parts.
He added: “The electrical interface of these parts operates at higher voltages (5V-80V) compared to a CPU chip, which only requires a low voltage switch or transistor (0.9V-1, 8V). Developing a technology platform capable of delivering the wide range of capabilities required by automotive chips has always been a challenge for the industry and can take 5-6 years, unlike the processor technology platform which typically takes around 1.5 to 2 years. However, this extra time investment can pay off in terms of significantly lower obsolescence rates – these chip technologies can last 15-20 years without having to be replaced.
Automotive chips require on-chip high-voltage switches or transistors. These transistors are called laterally diffused metal oxide semiconductors (LDMOS). Silicon LDMOS devices are a type of field effect transistors that can operate at much higher voltages than ordinary transistors.
They can also be integrated with billions of other transistors inside a chip. This requirement is also particularly important for space and defense applications.
Keeping these requirements in mind, the IISc team and its founding partner worked to develop a range of LDMOS devices (from 10V to 80V) with characteristics matching current industry offerings. The collaborative effort led to the development of a robust high-voltage automotive technology platform.
The technology platforms available in the industry have enabled the development of circuits capable of handling voltages ranging from 7 V to 80 V, considerably increasing the previous capacities of the national partners of 3.3 V.
Extending this portfolio to 80V by importing technology would have cost tens of millions of dollars. This collaborative effort augmented the core process and enabled the development of devices capable of operating at 80 V, at a cost of less than $0.5 million.
Professor Mayank Shrivastava (Department of Electronic Systems Engineering) who led the IISc project said: “IISc and its partners worked much like an industrial R&D team and dealt with fundamental issues differently, which which the industry usually deals with empirically (through trial and error). For example, we might dig deeper into some fundamental issues with these devices, like near-saturation behavior, which has not been fully understood/resolved over the past 40 years. Thanks to the IMPRINT program for enabling such a development which is proving to be a win-win for IISc and its founding partner.
Shrivastava added that the devices developed have been rigorously tested and found to be robust. “These LDMOS devices can now become standard offerings (like any other industry), which will help our foundry partner to develop a range of VLSI products in-house. Also, the technology or know-how can be transferred to other semiconductor foundries that want to upgrade their process from a basic CMOS to an automotive process,” he said.