By Ran Avinun
The military IC market is affected by recent semiconductor technology trends that are influencing the whole industry. Having particular needs for low-volume application-specific integrated circuits (ASICs) and specific reliability requirements make it even worse for the military applications designer to find an available solution. As the industry moves to 8-inch wafer fabs, throughput is improved tremendously, yet due to the added complexity and longer lead time of the fabrication process it becomes very expensive to process less than a full lot of 24 wafers as a minimum order.
With the continuous shrinkage of the semiconductor feature size, the military customer finds himself still using ASICs that are becoming obsolete. These ASICs were originally fabricated with technologies such as 1-to-3-micron CMOS, that are no longer available in production. Since the typical military customer requires longer product lifecycles and lower production volumes than commercial OEMs, the issues of military IC obsolescence has become critical.
The increasing challenges involved in servicing the military customer who has special requirements for high-reliability product testing and quality assurance is causing several ASIC suppliers to abandon this market, which forces their customers to look for alternative solutions.
Converting from obsolete ASICs
To address the problem of the obsolete ASIC devices, Chip Express of Santa Clara, Calif., provides an ASIC conversion service from discontinued devices. ASIC conversions are available from the gate-level netlists of LSI Logic, VLSI Technology, Motorola, Texas Instruments, and others. This enables the customer to receive the equivalent array, or upgrade the design and rapidly resume production. In addition, conversions are available from leading field-programmable gate arrays to lower unit-production costs for the OEM.
Chip Express officials have made their commercial ASIC products called Laser Programmable Gate Arrays (LPGAs) as a solution for the military OEMs. The Chip Express military program is targeted at satisfying the requirements for reliable long-production-life product together with low-cost, low-volume quantities and reduced development cycles.
Owing to their unique capabilities of rapid prototyping, such as laser micro-machining, and economically processing low-volume production quantities with their OneMask technology, Chip Express officials can offer a flexible program of low-cost ASICs for the military market. Providing military MIL-STD 883-B-compliant processing, Chip Express has become a favored supplier for military customers for aerospace, avionics, ground transportation, and satellite applications. The Chip Express military customer list includes: Lockheed Martin, ITT, Litton, Hughes, Rockwell, E-Systems, Allied Signal, Boeing, TRW, and United Defense.
Chip Express officials provide flexible ASICs that are screened to MIL STD 883, and have developed a flexible program to meet changing military market requirements. OneMask-processed devices, for example, are available that meet various military specifications.
Chip Express offers a cost-effective program customized to each military OEM`s testing and packaging requirements. The military program incorporates wafer processing in accordance with mil specs ISO 9002. While wafers are processed at the Chip Express facility, qualified 883B assembly vendors handle plastic or hermetic ceramic packaging. The product is burned-in and screened to the military standards that the customer stipulates. Chip Express offers full and partial MIL-STD 883B screening to Method 5004 and QCI to Method 5005 (groups A through D).
To provide military customers with fast turnaround and low-cost gate array fabrication, Chip Express uses two core technologies, Laser Prototyping and OneMask. The base array is fully metalized at the foundry, providing generic wafers personalized with a unique disconnect methodology. Using the same base wafer and layout for LPGA prototyping and OneMask provides a quick and seamless migration to production.
LPGA prototypes are customized one die at a time using a patented laser disconnect-methodology, and can be delivered in one day. Low-volume or early production quantities are available using the OneMask technology that enables designers to customize one wafer at a time using a single-mask, single-etch process.
In addition, OneMask-processed devices come without costly mask charges; only one mask is needed. With these technologies, the advantages of conventional masked gate arrays - speed, density, and low unit cost - are retained, and combine with the time-to-market and flexibility advantages of programmable logic. The ASIC production devices processed by OneMask can be delivered in one week. Military testing will require additional time.
Engineers at United Defense LP in Santa Clara, Calif., used Chip Express products to fabricate the V-NET high-speed data bus interface ASIC for their advanced vetronics applications.
"The selection of Chip Express as the United Defense fabrication house of choice for our V-NET ASIC was prompted by the fact they were the only ASIC manufacturer with embedded SRAM capabilities, VHDL design input, VHDL gate level simulation, and low-cost NRE," says Ronald Meadows, Staff Engineer in charge of the V-NET project at United Defense.
"United Defense has continued to use Chip Express for low-rate production of its V-NET chip in military grade," Meadows says. "As a defense contractor our production volumes are low, and product reliability requirements extremely high. Chip Express provides both of these characteristics for United Defense-developed ASICs. As an engineer with United Defense I have been extremely pleased with the Chip Express `Can-Do`; attitude, it is very hard to find an ASIC house that still accepts military business."
Ran Avinun is product marketing manager of Chip Express in Santa Clara, Calif. He received BSEE (1987) from the Technion (Israel) and MSEE (1993) from Tel-Aviv University (Israel). For five years, he was involved in the EDA industry working as senior application engineer with Daisy Systems and Intergraph Electronics. Avinun joined Chip Express in 1993 and worked as senior application engineer and testing manager for three years. Last year he was promoted to his current position.